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Nightmare watched in envy, the darkness around him concealing himself and his aura. He watched from the sidelines how red made blue happy.
Red was a regular monster; a mortal. Just like blue. He has a somewhat comfortable universe to reside and spend his time in, just like blue. He has a loving brother, a normal house, and friends just like blue.
But thing was– blue was out of his league. He was strong, confident, determined and so so much more.
He's been head to head with God's; testing his strength and coming out alive and well. His soul's magic stronger than nightmare has seen in any mortal.
Blue was no normal monster. He was extraordinary, he was unique, he was…..beautiful.
Nightmare first noticed blue the second day he had joined the stars. Nightmare didn't think much of him; just another replacement, as he recalled. Blue had proven himself worthy when had the power to take on killer, Dust, and horror and come out of the dust of fog still smiling and making jokes towards ink.
Nightmare’s fascination started at that point and only grew from there. That beautiful color blue slowly infecting his mind like a virus. A virus that he knowingly implanted.
He watched blue every chance he'd get. Whenever the stars appeared in an au that him and gang was wreaking havoc in, he’d sit in the shadows and call back the others just so he could watch blue. Study his emotions, his face, his clothes, his body .
Eventually cross and killer noticed, his two most trusted men. When first questioned he'd use the excuse of wanting to ambush them or letting error get to them first to tire them out but he knew the two weren't buying it.
It was when he had finally had the chance to go face to face with blue alone.
Error was in a particular spicy mood that day, pulling no bs when it came to the stars intervening on his work. Dream was down and ink was hanging on by a thread. The only thing that was keeping him up and still full of energy was the red paint that sat in his system.
Blue had managed to avoid the glitchy but dangerous god. He couldn’t hold off error as he would surely overpower him instantly. The only other ringmaster there was nightmare.
He was off to the side, still watching blue while also checking in on his gang. He didn't notice the blue clad skeleton teleporting directly in front of him before landing a solid hit to his head.
He remembered the joking remark of how ‘he needs to keep a closer eye on his enemies’ and how he tried his best to make it look like he wasn't holding back when attacking his new obsession. The glimmer and pure mischief in blue’s starry eyes, his bright and determined smile, his strength and agility.
Nightmare was in love
From then it only got worse; “dangerous” as cross had put it. He went from watching blue when he was conveniently in the same au as him, to traveling the multiverse just to see him from the shadows. He watched–studied him and his brothers’ dynamic. He knew what specific order of seasoning blue used on his tacos. (once even stealing one for himself) he knew blue's favorite song at the rave, his favorite color, his lucky pair of socks, his insecurities, what kept him up at night.
Nightmare spent his free time stalking blue like an obsessed ex. His mind only filled and wrapped around the strong mortal. The thought of blue even looking his way outside of battle made his corrupted soul flutter.
He understood where Cross said that this could be dangerous. An immortal God obsessing over a mortal was unhealthy– wasn't normal. Then again when has anything been normal? There was also the chance of dream finding him in underswap, lurking. The only one who could feel his aura over the cover of shadows was his annoying twin.
His obsession turned into envy– a dangerous feeling for him– when he found out about blue's secret lover: red; an underfell sans variant.
Just a normal sans with no discernable personality that really differentiates him from classic other than the fact that he's emo and edgy. He was lazy– a slob. He didn't travel the multiverse like blue did, he didn't have extraordinary magic like blue did, he didn't have anything on board with blue that made him unique.
Blue wasn't meant for red. Nightmare could see it. Blue wanted someone who could make his life interesting, give it change. He wanted liberty– something or someone to break the cycle that he's created for his life. Instead here's red: a reminder of blue's life back in underswap, basically identical.
Yet, somehow, blue still loved red. He would smile whenever he got a notification from red messaging him, he would hug red when ever blue snuck out of his Au to see him. Even when blue wanted to take thier relationship ship to another level, red refused. And yet blue still smiled and nodded his head in understandment.
Nightmare hated red
He didn't give blue what he wanted– needed . He needed someone who would treat him like an empress. Someone who would kiss the ground he graced his boots with. Someone who would listen and obey to his every demand.
Blue needed Nightmare
Over the next year nightmare had found a way to talk to blue without him being there physically: his dreams. It was risky but nightmare couldn't care less as he got to see his soon to be lover every night.
At first blue was scared, nervous, and untrusting; everything nightmare didn't want blue to feel towards him. Eventually blue stopped flinching every time he heard the darker’s voice ring in his lucid dreamt world. Instead, nightmare was greeted by his name. A simple “hello, nightmare” or “hey octopus” made his body laxed and soul thumping.
They talked until blue woke up. They talked about anything and everything. Their past, random subjects, food, magic.
They were similar in so many aspects– puzzle pieces that fit together perfectly.
Nightmare grew bolder, confident. They began diving into more personal topics. Blue's dating past, personal and intimate questions, red. Nightmare wanted to know blue in and out. He needed blue to understand and know that he understands blue more than anybody in the multiverse.
He began to plant the seed. The seed that would eventually cause blue be uncertain in his and reds relationship. Be the cause of that glimmer that would always appear whenever red was near; disappear.
“ When was the last time he'd given you a gift unasked?”
Nightmare knew the answer. 8 months, 1week. And 3 days. Red was never truly considerate. He was selfish and that was coming from nightmare. He may be the king of negativity but he knows how to treat his partners and make them feel worthy.
Blue hummed at that question. His blue eyes deep in thought as he looked Into the horizon of his dream.
Blue had dreamt of a quiet place. A clif that was hovering over a beach. The sunrise creating a beautifully soft orange glow as the soft waves crashed with the white sand below.
“I don't know”
He finalized. His mouth was pulled into a slight frown at the realization before he forced a smile back.
“But he always remembers to give me a birthday gift”
‘He only remembers because you have to write your birthday on the calendar every year’
Was what he wanted to say. He wanted to give blue the full picture– the full understanding on how little red cares.
Nightmare almost slipped up if not for the absolute distraction that blue's beauty provided. The orange sunlight lighting his face, painting a picture that aphrodite would have painted herself.
“ I mean it's not that big of a deal I guess. How many times would you gift your partner?”
Blue snorted as if nightmare’s concerns were silly, unserious.
“Everyday”
Nightmare hummed
“ Just for existing ”
Blue stopped his momentary giggling to stare.
“Seriously?”
Nightmare slowly nodded; a short. Non vocal answer to blue.
“ Where I'm from, we were taught to treat our partners like the finest wine; savoring every taste and moment. Especially as a God I was told to treat my partner like my soul mate, because they are–”
He and blue held eye contact— unbroken. The sunrise rested between them in the distance. It looked like a postcard you'd see on someone refrigerator– dream-like, unreal.
Blue breathed a quiet ‘wow’. His eyes, a shiny blue, still locked on to nightmare as if he was waiting for more.
“Do you…have that someone? Soul mate I mean”
Blue spoke quietly as he finally looked away. He was cute, nightmare wanted him so fucking bad.
“ I don't, but I'll find them someday ”
It was almost time for blue to wake up, they both knew it as nightmare noticed a small pout that blue held for a second. He felt a little rush of confidence, having one of his black tendrils gently guide blue's gaze back towards him by the chin.
“ I'll see you tomorrow”
He purred. He could feel that sudden burst of fondness, his face true to his name as nightmare refused to let him look away from him.
This was intimate. The most intimate nightmare has been with blue so far. For a guardian devoted to hatred, he felt nothing but love.
“Later, darling”
Blue's thoughts started to give him headaches.
He and Red were happy, right?.
Sure the other could be a sleazeball sometimes, and yes he barley called or checked when blue was in his own au. But it was fine.
Nightmare obviously thought otherwise. Though, blue didn't care about what other had to say about him and red. Most monsters from both his and his boyfriend's au would say how ‘unfitted they are’. It was annoying but blue never listened. It was just something in the way nightmare had worded his concerns over him and red, they seemed reasonable. Especially with the relationship standards that nightmare was raised in.
They were unrealistic, for blue at least. But that didn't stop him for comparing everything that Red did to what nightmare described what he would do.
He noticed how little red would want to cuddle with him or even touch him. Blue was a very physical person but understood boundaries,but, the thing was that— red was also a physical person from what blue understood. He always hugged his brother or classic, and so on. So why did it stop when it came to him?
Another thing that blue noticed how inattentive red was. Blue loved to show out and go out of his comfort zone for someone he loved, especially red. Though they never went beyond making out, blue would wear skimpy outfits he heard red talking about, indulged and hinted at some of red’s fantasies but no matter what it would be dismissed. Blue shook it off to red just being oblivious but the more he thought about those instances, he grew more frustrated.
He felt bad for criticizing his boyfriend so much. He’s never criticized someone so much ever in his life so why now? He didn't understand. Whenever he looked at red— his supposed soul mate— he couldn’t help but get a feeling of such annoyment.
Selfishness
He voiced his thoughts to nightmare once in one of his lucid dreams. The god sitting and letting blue rant about how disgusting he was making himself feel with the sudden degradation towards his lover.
Nightmare refuted the claims of blue thoughts even being considered selfish. He praised him; called him selfless and understanding. Kissed the back of blue’s knuckle and told him just how priceless his attention and beauty was and how red was an undeserving monster of both.
It was mean, but blue held onto it. He held onto all of nightmares words like a lifeline. The voices of doubt in his relationship sounded like the dark god’s deep voice— soothing and peaceful. The bright light that shone on red dimmed.
He still loved red, that small feeling never being able to escape his soul, but nightmare was right there . Blue saw how the deep and brooding god was more than what other perceived him as. He was charming, generous, persistent, handsome— Blue would be lying if he said the soft gaze that nightmare always directed toward him didn’t have an effect.
He wanted to see nightmare in person. Feel that dangerous aura radiating off of him— feel how cold his corruption is to the touch. Nightmare, of course, enthusiastically agreed. He’d never seen a being filled with so much negativity be so happy.
He sat on his bed thinking about what he was going to do. Was meeting and having feelings for another monster considered cheating? He wished he had his handy dating manual with him, but something told him that even if it was arm's reach he still wouldn’t have read it.
Blue was nervous— it wasn’t everyday that you had a chance to meet up with your sworn enemy. What would happen if dream caught him or ink? What if omega frisk popped up at the worst time possible and snitched? So many things that could go wrong— yet— all blue could really focus on was seeing the god outside of his dreams.
Nightmares had given him a code to a specific Au. It wasn’t a very well known Au but it wasn’t secluded either. A story shift Au, specifically one that had been through a genocide route; a negative Au that was nighmare’s teritory.
Sighing, Blue stepped through the formed portal he created before it closed behind him. The Au was bright, unusually bright for a universe under Nightmare’s control.
It was bright enough for blue to be able to see nightmare just short in the distance. He was still as intimidating as he last remembered in battle, but with his new fondness, put him in a batter light.
Blue swallowed as he stepped forwards to be closer to nightmare; a strange aura drawing him closer than he wanted. It just felt right though, finally being close to nightmare after only seeing him in the dream world for a while. It made him feel…antsy and tingly, though blue could not place a proper name to what he was feeling.
Eventually nightmare came fully into view, standing directly in front of the shorter warrior. Blue noticed just how dark his corruption was. It glistened like the stars in the sky he saw in the overworld
“ You’re—“
Nightmare could barely put his thoughts into words, fumbling over his speech. It could be considered embarrassing at how flustered the god was but he didn’t care; couldn’t care . He and blue had seen echo their hundreds of times whethe that be in the dream world or in battle. Every time nightmare got a chance to see him he swore that the bright light radiating off of blue only grew brighter and brighter.
“Beautiful. Even more so in person”
He breathed, his eyes half lidded as if just the sight of the warrior alone was an aphrodisiac drug— crawling into his ribs and wrapping itself around his spine in th most seductive ways.
He wanted- no. Needed blue and he wanted him to understand that much.
Blue’s face became true to his name. His eyes shying away as he let out a soft chuckle. He ducked his head down into his blue scarf in an attempt to hide his brightening blush but to no avail. He was weak for compliments— praises. Some of the things red barley gave him. He wondered how many times he became this bashful around red.
He quickly waved thoughts of his boyfriend away, not wanting to ruin the mood he and nightmare had set.
Nightmare looked hungry— needing. His eyes following blue like a predator stalking it’s prey. That singular teal eye sharp like a cat’s and twice as dangerous as a tiger’s. Blue should be freaked out or at least worried but he couldn’t find it in himself to be. Instead he felt enthralled, a tug on his soul leading directly to the corrupt god in front of him.
He had never felt so connected to another monster before. The more he lost himself in that sea of teal, the more he felt himself let go. Let go of what? He didn’t know but he was grateful. He couldn’t think about the disapproving words of dream or the pain and annoyance red has caused for him. Just nightmare
Only nightmare
His mind didn’t feel like his own, floating on top of a cloud as he let his body move in what ever ways it wanted to. He felt a weight lift off his should at that name: Nightmare .
He could only see, think, and feel nightmare. Just nightmare.
His usually bright and starry eyes shifted. Not enough to show blatant change to the naked eye, but visible to nightmare. Blue— his blue— needed him. Wanted him and only him. Not dream, not his brother, not red. His soul flared with a new found emotion he couldn’t put his hand on. Whatever it was, it was electrifying— exciting.
The tips of his tenticles curled in on themselves as they attempted to release some of this emotion. They wanted so bad to wrap around thier new prey. Play with him and touch him until he is body couldn’t bare it anymore. He wanted to feel blue inside and out, connect thier bodies and souls through intimacy. Such a sacred practice.
They continued to stare at each other. Blue being out of it; wanting for nightmare’s voice to tell him what to do next, and nightmare still indulging on the pure beauty that radiated off of him.
He opened a portal behind him, the darkness eminiting from the castle a stark contrast to the pearly white snow. Nightmare reached for blue’s gloved hand, raising it towards is mouth and planting a chaste kiss. He watched as blue’s face once again lit up, his pupils forming into stars.
‘So easy to please’
Nightmare smirked before he, reluctantly, tore his eyes away leading blue into the portal that lead to his castle. As the portal closed behind the two, he noticed just now quiet blue was; something that was out of his nature. It freaked him out for a second, scared that his plan wasnt working until he remembered one crucial thing.
”you may speak”
Commands. He had never been gifted a power like this before. Sure, he was a king, an emperor, a tyrant, a guardian; he had plenty of power. But having power over a soul was something different . Something exhilarating.
“Why are we here”
Blue’s determined but curious voice rung through the cold, chilling air of the dark hallway.
“This is your new home”
He saw the slight confliction in blue’s demeanor from the corner of his one good eye.
“Our home?”
Blue was adorable. Blue was magnificent. Stars, nightmare was lucky to have such a precious gem in his custody.
Nightmare laughed, a deep feeling of satisfaction wrapping itself round his soul.
The rest of their walk was filled with comfortable silence as one of the king’s tendrils wrapped protectively around blue as if someone would come and steal him. Blue belonged to him. All of his attention, devotion, love, rightfully belonged to nightmare.
The walk was long, yes nightmare could’ve taken a short cut to his bedroom, but, he wanted to show off his achievement to his gang. Not saying a word as he passed through the living space of the castle that was way too big to only belong to 5 monsters. Blue didn’t spare not one glance towards the others, only keeping his eyes on the path ahead of him or solely on nightmare.
Nightmare opened the door to his regent room fit for a king and his pet. He stepped aside as blue entered behind him, his face struck with awe at the lavish room. Nightmare damn near slammed the close behind him. His body ached for thier long awaited connection, as he could feel how impatient his magic was getting.
Blue stood patiently in front of him, waiting. He knew what nightmare needed— he just wanted to hear it come from his mouth.
” strip”
His voice dropped an octave, lust pooling into his mind every passing second. Just the sight of the blue warrior turned him on in unimaginable ways. His pristine white bones, decorated with scars that told a story was a sight to behold in of itself.
Blue was slow, deliberating— calculating— when taking off his clothes. He knew the effect he had on nightmare, being quick to take his shirt off and expose his ribs, but slow to take off his shorts as his own magic began to form.
His etco snapped in place leaving him fully naked, bare, and wanting. His fully formed female body entranced nightmare, pulling him into his own state of hypnosis. He didn’t dare break his gaze away from blue face, his bed room eyes telling his own set of commands.
Nightmare groaned as his own etco formed. His hard cock throbbing in his pants aching for blue and only blue. He watched how blue slowly sat the bed ever so gracefully, the small rolls on his etco stomach making nightmare drool like a hyena who hasn’t eaten in months. To say he wants to devour blue would be an understatement.
No words were exchanged; they didn’t need to be exchanged. Why use words when thier pure, raw, emotions spoke for them. Nightmare’s body moved before his mind could conjure it’s next thought, his legs stopping at the base of the king size bed where blue sat in all of his glory. His cock twitched at the sight before him; his fascination presenting himself for the king ready to be devoured and wrecked while at the same time preserved.
Nightmare’s hand made contact with blue’s puesudo thigh. Blue visibly shivered at the contact, whether it be from nightmare’s natural ice cold body temperature or from arousal. His pussy gleaming as it was already wet and wanting. All of blue now belonged to nightmare, and he knew it.
His legs voluntarily separated as nightmares hand hacked up his thigh to where it met his hips. Blue’s eyes were trained on his hand, watching it as it dipped between his legs teasingly, before beginning to caress his begging clit.
His hand felt like magic, moving in small calibrating circles. The tips of his fingers teasing his wet entrance every now and then. Blue saw how nightmare studied him, his sharp eye solely focused on blue's glowing face with concentration.
He wanted nightmare to have him– all of him. He needed Nightmare. A small man escaped his mouth as the now warm hand on his pussy began to go at a faster pace; his clit being played with like a turning table.
Blue's mouth opened with a quiet moan, his body begging to shiver as the pleasure was slowly, but surely, building up. He remembered how lonely his nights would get. How he wanted nothing but to experiment pleasure brought by his partner.
At least now he has nightmare, his hand telling blue how much he understood him– how much he dreamed of being wanted the same way he's been wanting.
The smaller’s voice piqued in volume as one digit was slowly introduced into him.
“Fuck-”
One finger was all it took to unravel him– expose him and tell his dirtiest secrets to the king. He wanted more. He's never wanted anything more than he has before now.
Lifting his hips as much as he could, he grinded down on that singular digit. He huffed as nightmare slid in a second digit to the knuckle, his palm resting on his clit.
Stars, he needed this. He didn't realize how much he needed nightmare’s calloused fingers to scissor him, brushing against his g-spot in the most blinding ways as he pumped them in and out.
Blue wanted to cry. He had never felt such pleasure before. He thanked whatever God's out there that blessed him with such. He watched as his magic coated the dark hand, eliciting a shaky moan with each pump.
“Nightmare-”
He gasped as he felt a familiar knot in his stomach. Blue whimpered as nightmare's advances didn't slow down, instead sped up.
“Stars you're gorgeous”
Nightmare leaned down to his neck. His breath warm against his sweet spot as he licked a long stride across his neck to his jawline.
“I want you to cum for me. Can you do that”
His voice was breathy, trembling as he was watching the best show possible as his clothed cock nudged against blue's thigh.
It didn't take long for blue to follow command; Nightmare’s fingers abusing his g-spot with such tenderness that made his tears spill over and back arch. His body tensed as moaned nightmares name like a symphony. Shame he couldn't see how his magic decorated nightmares palm as he came.
Nightmare pulled his fingers out, drenched and soaking but leaving the king satisfied with his product. His cock twitched in excitement, begging to finally release himself from confinement.
He let out a shuddering groan as he pulled down his pre-cum soiled pants, feeling the cold air hit his erection. His teal magic was a beautiful sight. Gleaming and ready, he's never been truly proud of anything until this moment.
Without hesitating or even a second thought, he aligned his aching cock with blue's dripping pussy as dark tendrils snaked from behind nightmare to wrap around blue's thighs. It truly was a sight to behold. A sight that only nightmare will get to enjoy.
Blue was completely and utterly vulnerable– at the king's mercy. His pussy on display waiting, begging even, to be filled with nightmares cum. His back planted firmly against the expensive mattress as his legs were held apart by corrupted tentacles.
His eyes were glossy, tear stains down his cheeks, chest heaving just the slightest bit from his first orgasm.
Nightmare almost came at that moment. Just from taking in the sight of blue.
“Fuck- look what you do to me, blue”
His hips bucked, forcing an inch in without any warning whatsoever. The warmth and tightness that blue gave almost pushed the king to the edge. His body swelled with pride as blue whimpered.
He paused, waiting for blue to adjust before he finally gave into what his body craved– what they both craved. Nightmare couldn't help but look blue in the eyes, those deep lights of blue telling him all the words he wanted to hear.
He knew red wasn't the one for blue– he wasn't worthy, wasn't deserving. Blue needed everything good in the multiverse, someone that could give him everything he wished and more.
Blue's eyes rolled to the top of his head as nightmare shoved the rest of his length in. His walls fluttered at the feeling of being so full– so good in a way that no one has ever made him feel like this.
He was his – truly and utterly nightmare's.
He wondered what kind of luck he had been gifted. To be wanted so much by a king– loved and cherished like a family heirloom. His spine shivered as nightmare fully bottomed out. His pseudo flesh making contact with blue's, the natural coldness that nightmares body held sent yet another shiver down blue's spine.
Nightmare was big , his cock nestled comfortably inside of the younger. He needed this. Yearned for this even for however long; to be connected to blue in other ways than just emotionally. He needed to be one with blue. He needed blue to want to come to him when he needed something. He needed blue to be dependent on him- to never want to leave the comfort of his castle.
“ Stars, you are one of the most beautiful monsters I have had the pleasure of seeing”
Nightmare was entranced. He had more power, more influence, more money– but fuck – did blue have him wrapped around his finger without even knowing. Nightmare would do anything for him.
“ Promise me– Promised me that you'll be mine. I want to be yours, blue ”
He was begging. A king never begs, not for no one, but blue is an exception. Nightmare would domesticated himself inorder to please blue. He'd worship the ground that he walked on, kiss the fine China that he used, drink the water he'd use to bathe in– he needed blue in every way and blue needed him.
“please take me”
Blue breathed. Nightmare hadn't begun moving but blue was already approaching his orgasm. His azure eyes hazy, filled with pure desire and hunger. His mouth gaped open as drool seeped out. He was already in bliss, that's just the type of effect nightmare had. He may be a being of negativity and everything hateful in the multiverse, but stars did he make blue feel like the only monster in the world.
Some part of him was happy, grateful even, of nightmare taking him away from red. He never made blue feel this good– this wanted ever in their relationship. Maybe red didn't love him that much, at least not in a way that nightmare does.
Nightmare pulled out, just before the tip. Feeling how tight blue's walls were before delving back in with a soft but swift pace. He could feel his bones rattling as blue cried out. He wanted to hear more. Hear that beautiful voice of his moan his name.
His hips bucked once again, slow but deep until his etco was completely adjacent against blue's. Nightmare didn't set his pace immediately– instead he savored the feeling of being so deep, so connected to blue. He couldn’t wait to fill him with his cum, see that beautiful face twist in pleasure and pure satisfaction.
Nightmare leaned down as he captured blue in a long but passionate kiss, their tongues dancing alongside each other as their groans vibrated through each other's body. His pace a mixture of both desperation and adoration, pulling out to the tip in a swift pace but rocking his cock back in to the hilt with such carefulness.
His seams started to unravel as he was teetering on the edge already; blue's moans and wails contributing to his nearing approach.
The sounds of their wet echo meshing together and blue's continuous moans filled the quiet room– a beautiful symphony that nightmare wished he could play on repeat and never stop.
Blue cried out as he came for a second time, reaching up and hooking his hands alongside nightmares back careful of his tentacles. His nails dragging down nightmares spine from the overextension of pleasure his body was encapturing. His walls tightened as blue magic painted his lover’s abdomen and glistening ribs.
It was like heaven and earth came crashing down on the king. He wished he had the chance to experience such groundbreaking pleasure before. His vision turned to white for a moment; mind going blank as his cock pumped loads of cum into blue’s abused pussy.
His hips stuttered to a stop, not wanting to overstimulate him or blue.
“God damnnit”
Nightmare groaned as he started to find himself again, blinking out the white spots that clouded his vision. His tentacles behind him shuddered, momentarily thrashing silently before calming down again.
Blue laid underneath nightmare looking absolutely spent. His eyes half closed in exhaustion as his mouth gaped open trying to inhale additional oxygen. His bare chest, on full display, rising and falling. He was ethereal.
Nightmare pulled out after he finished soaking in the god-like form that blue held to him. He wanted to sit and stare at blue longer but the feeling of sweat and cum sticking to both of them wasn’t such an appealing thought.
With quick thinking, nightmare carefully picked up blue bridal style with his tendrils as he brought him to the master bathroom connected to his room.
The warm water felt amazing on him and he knew it felt good on blue as well. That content, happy, and satisfied look on blue’s face told him everything.
He couldn't wait to worship blue for the rest of his time.