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It was always something about the other professor that had Byleth wondering if something was up. Something in the way he presented himself – something about how he was always so standoffish, so cold towards Byleth… it had ignited a fire in Byleth. One that had burned in his stomach, licking up his chest like a flame growing in intensity with every passing day.
It’s one day that they’ve had a small tiff that Byleth decides to corner Seteth about it. They’d fought about battle tactics, yet again, and Seteth had deemed the conversation ‘over’ and ‘unnecessary if you aren’t going to listen’. That had been the final nail in the coffin, and what spurs Byleth to stalk after the older professor, now.
Seteth, Byleth finds, is never one to immediately lock his door when he’s in a foul mood. He finds Seteth in his room, the door open slightly ajar from where it hadn’t locked as he’d swung it closed. He stares in, half wondering if this is an invasion of privacy, or if he’s totally justified in barging in and demanding Seteth listen to him in the ways of his tactical plannings.
It’s when Byleth watches Seteth take off his cloak, unbuttoning his outer shirt that makes Byleth pause. He watches for a second more how Seteth gently places his shirts and cloak over the back of his high backed chair, before he’s marching in quietly and shutting the door behind him.
Seteth turns at the sound, his face shocked yet… there is a darkness of something… more. It makes Byleth’s heart race and his loins stir, as he looks over Seteth’s bare chest, where there’s the dense forest of green curls over his chest – trailing all the way down to… Scales?
“Byleth – what is the meaning of –”
“What are those?” Byleth cuts him off, and Seteth’s face flushes as Byleth takes a firm step forwards. He watches how Byleth stalks him, those unwavering eyes always on him, a hand outstretched until gloved hands find him, touch him, and he’s shaking beneath the criticism of that steadfast gaze…
“Are those… scales?”
Seteth’s face burns bright, obviously uncomfortable with the way that Byleth stares at him. He tries to back away, but his back is against the desk in his room. He bumps into the hardwood, knocking over a few books, jostling a jar or two, scattering papers. Byleth continues to push forwards, pressing into Seteth's space, his hand dragging down the older man's abdomen.
“Seteth… what are you?” Byleth asks, kneeing in between Seteth's legs, crowding his space until they are literally breaths apart.
“Something you cannot fathom…” Seteth's voice wavers, his stomach leaping as Byleth’s fingers tail down over the scales. Ever downwards, traveling ever forward, no end in sight to his searching.
“Byleth… We can’t – not here…”
Byleth stares with wide eyes, his hands trailing over scales and muscle, alike.
“So this is what you’ve been too scared to show me.” He says, and Seteth makes a guttural sound in the back of his throat, a bit of warmth licking up out of the corners of his mouth. Byleth can see now the missed cues that would have given Seteth away earlier – if only they’d had the thought to look.
Seteth’s eyes are narrowed – slits breaking through green like thunder, yellow rimming the edges like wildfire. His mouth, open just a bit to emit that warmth, shows the very glimmering starts of fangs. Teeth pulled out, gums showing as he snarls at Byleth’s forward touches. It makes Byleth hard in his pants – the thought of being ravaged and marked by those teeth.
He’ll have to ask Seteth about that later, though.
Another time.
Seteth’s hand comes up to lay on Byleth’s shoulder, a small quake to his movements that only seems to dim once they’ve made contact. Byleth wishes that it were skin to skin… but again, that’s for another time. He quickly takes his glove off with his teeth, letting the fabric drop down to the floor as he replaces his hand to Seteth’s stomach, feeling now the roughness of Seteth’s scales.
“Like the dragon rider's steeds…” Byleth mutters, more to himself than the room, and Seteth shudders at the observation. He tries to move away from Byleth’s wandering hands, but Byleth catches his chin between his fingers and turns him back to stare into those unwavering blue eyes. Seteth’s own eyes refuse to focus on one aspect of Byleth’s face, darting from his lips to his eyes, back down until they are mere inches away from each other.
Byleth lets their lips touch, grazing over the older man’s until he takes Seteth’s lower lip between his teeth, tugging lightly. Seteth can’t help the way that his body melts into the touch – as if he’s never allowed himself such a thing – and Byleth warms into him as they clash together to deepen the kiss. Pawing at each other, Byleth’s ungloved hand reaches down between them and begins to undo the amount of belts that Seteth wears, his ceremonial robes falling open as he finds Seteth’s pants and shoves his hand inside.
He finds Seteth’s cock hard, pulsing between his thighs, and Byleth smiles beside himself as he takes the entire girth in his hand and starts to pump with a rhythm that mimics their shared heartbeats.
Seteth himself seems to breathe fire, his breathy gasps hot against Byleth’s face, carving its way down his throat to rest between the armor that Byleth wears and his skin.
Byleth leads them both to the bed – their lips ever entwined the entire way there, and Byleth shoves Seteth onto the fluffy comforter with a forceful hand. He clamors on top of the other Professor before Seteth can regain his bearings, ditching his own pants as he practically tears Seteth’s own clothing off of him.
“Byleth – wait!” Seteth tries to warn him, tries to explain the sight that he sees before him – but Byleth simply stares in awe, his mouth practically watering as he takes in the monster of a cock that he sees before him. He’s never taken something as big as Seteth, but Byleth wouldn’t consider himself a quitter – if his experience using his time reversal technique is anything to go by.
Kneeling atop the other man, Byleth decides to put his mind to it, and rubs himself all over Seteth’s slobbering cock. The other man is making so much precum that it coats Byleth’s hole easily, catching the head on the rim, causing Byleth to moan out load. Seteth tries to shush him, but he only manages to make Byleth moan more with heavy hands on Byleth’s waist.
The stretch is tight – Byleth’s body threatening to break as he lowers himself on top of Seteth, his knees giving a slight twinge of pain as he inches ever faithfully on downwards. Seteth’s face is half covered with his hand, but not enough where Byleth can’t see the grinding of his sharp teeth, letting out the groan of undeniable pleasure that wracks through him as his cock fills the younger professor up.
Byleth’s hands grip at Seteth’s chest, groping for purchase as he bottoms out on top of Seteth’s cock. They sit like that for a while, melting in each other’s warmth, before Byleth begins to set a pace that has them both fighting to keep quiet. The students would be getting out of classes by now, and anyone could walk into the Professor’s quarters at any minute. The chance of being caught excites Byleth even more, and his own cock begins to leak all over Seteth’s stomach as he begins to feel something growing against his ass. He looks behind himself, pulling again at his ass to move the muscle out of the way, and begins to watch Seteth’s cock swell and bulge in a new, fascinating way.
Byleth’s eyes glimmer as he thinks about what it is that is currently stopping him from taking Seteth down to the hilt, and his movements renew with a vigor that has Seteth writhing in pleasure that bleeds over into overstimulation.
“The knot…” Seteth pants out, “You’ll hurt yourself.”
Byleth can’t help but take that as a challenge, and he wills his body to relax, aching as it is. He slides down Seteth’s length, practically begging for Seteth to go faster as he feels claws begin to sink into the leather bracing at his side. Byleth thanks his stars for the armor – knows that if he didn’t wear it, Seteth’s extending claws would be tearing into flesh as they move and breathe in unison… and the thought exhilarates Byleth even more. He moves his hips at a more fervent pace, chasing after his own ecstasy, too.
He looks down to see Seteth’s facial features morph – changing to further demonstrate just how inhuman he is. Scales dance across the contours of his face, his eyes narrowing to slits and the beginnings of horns breaching his forehead.
Monstrous.
Intoxicating.
Byleth swoons as he reaches around to pull at the meat of his ass, opening himself more for Seteth’s monstrous cock to split him open wider, fuller, deeper.
His hands never leave Seteth’s chest, massaging the breast tissue ever more fervently, plucking at the pert nipples as he rides Seteth with a deep zeal. It causes Seteth to whine, his cock twitching at each pinch and twist, causing Byleth even more pleasurable sensations as he rocks himself back and forth.
Byleth comes silently, biting his lip so as to not bring attention to themselves, and the clenching of his insides causes Seteth’s eyes to flare open wide, his musculature changing drastically as he grips Byleth with clawed fingers and forearms that threaten to bust out of his tight sleeves. He punches his way into Byleth’s ass, filling him up with his cock until he locks them together with his knot, spilling inside of Byleth with a strained roar that never seems to end. It causes Byleth to shudder as he feels himself be filled, and he remains seated as best he can to hold all that Seteth has to give him.
They stare at each other for a brief moment – Seteth’s more draconic features unmitigatedly pointed up into the deep pools of Byleth’s eyes. Byleth’s chest constricts at the elder Professor’s change – but not out of fear. Understanding, maybe. But not fear.
He catches his breath before Seteth does, and the two of them are about to speak when they hear a knock at the door. The two of them freeze as Manuela’s voice breaks through the wooden door.
“Professor Seteth? Are you alright? I heard the most ghastly noise just now.” She calls out, and Seteth’s entire face goes a bright shade of crimson as he coughs, gathering himself.
“Yes, Professor Manuela – I am alright. I just… got heated about a subject. I apologize if I made a nuisance.” He calls back, and Byleth lets a small smile slip across their features as he makes himself cozy on top of Seteth’s chest. They are still connected, the knot not planning on deflating any time soon, and Byleth can hear Manuela huff as she calls back.
“Well, as long as you are alright. I’d be wise to keep your studies down – the students might get curious!” She warns, and it’s Byleth’s turn to pale at the thought that someone had seen them enter Seteth’s room together. He hears the click of Manuela’s heels disappear into the distance, and once the coast is supposedly clear, he turns his attention back to Seteth.
The other man’s features are starting to revert back to their more human form, and Byleth places his hand on Seteth’s cheek, rubbing at the remnants of scales that linger there.
“So – you’ve got a lot of explaining to do.” Byleth teases, and Seteth sighs as he rearranges himself. He knows that they’ve got a lot of time to kill, now, and the best thing he can do is start from the beginning.