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The hushed tones of the Ubuyashiki Mansion were broken by a commanding voice. “Insect Pillar, Kochou Shinobu. Kneel,” ordered the ex-hashira, her gentle and soothing smile gone from her face, making her intimidating.
The young hashira dropped to her knees without hesitation. Determination etched across her features, she had prepared herself for this hashira meeting. Instead of her usual haori, she wore a simple kimono—a stark reminder that she stood ready for trial. Her back remained straight, and her clenched fists revealed her unwavering commitment. As she glanced around, she met the worried gazes of her teammates. Kanae, her elder sister, rarely showed anger, but everyone understood the gravity of the situation.
The tension in the room was palpable, but Shinobu’s resolve remained unyielding, even as Kanae circled her like a hawk assessing its prey. The younger hashira’s clenched fists trembled slightly, but her gaze never wavered. She had made her choice, and she would face the consequences with unwavering determination.
Kanae sighed. Her sister was tough, but her tendency to push herself to the limit would be her greatest weakness one day. Not that Kanae was not confident about her sister, but with Shinobu’s size and strength, demon slayer was a job far too dangerous for Shinobu. She was proud that her sister became a hashira. She was relieved that Shinobu could take her back from Douma and revive her. She was glad that she could see Shinobu again, but what Shinobu did to revive her was far from acceptable, for her and for the Corps.
Her voice was stern, yet carried a tinge of sorrow, “As the ex-hashira of the Kisatsutai, it is my responsibility to teach you to prioritise the organisation’s goals over your own.” She reiterated, “Reviving me with the Nezuko serum was a desperate act, Shinobu. But desperation cannot justify risking Nezuko’s safety or compromising our mission. We are demon slayers, not martyrs.”
Shinobu’s throat tightened. She had acted out of love for her sister, out of a desperate need to bring Kanae back from the brink of death. But Kanae was right—the Corps couldn’t afford such reckless sacrifices. The weight of her decisions pressed down on her, threatening to crush her spirit.
Kanae’s gaze softened, revealing the pain she felt as an older sister. “Have you thought of the Butterfly Mansion?” she asked, her voice gentle yet firm. “The swordsmen who rely on you as their doctor? Your absence would leave them vulnerable. We fight demons, but we also protect our own. Remember that.”
Shinobu’s eyes stung. She had always been the healer, the one who mended broken bodies and spirits. But now, her actions had jeopardised everything she held dear. She had betrayed the trust of her comrades, and the guilt was suffocating.
“Getting eaten should not be seen as a victory,” Kanae whispered, her words a fragile thread connecting the sisters. “I won’t watch you destroy yourself, Shinobu. Your life is not a bargaining chip. And your vendetta against Douma—”
“—is my burden to bear,” Shinobu interrupted, her voice steady. “I will not let my personal vendetta endanger others. But I will not stand idly by while demons roam unchecked. I will find a way to defeat them, even if it costs me everything.”
Oyakata-sama’s deep voice resonated, breaking the standoff. “Kanae,” he said, “Shinobu’s loyalty is unwavering. Her intention was good…”
The Flower Hashira stood resolute before her leader “I understand, Oyakata-sama,” she spoke, her bow deep and filled with respect. Yet, for the first time, she challenged the authority she had always upheld. “Her intention was noble, but her actions were reckless. As her Shihan and her nee-san, I cannot condone her plan. Shinobu must face the repercussions of her actions.”
Oyakata-sama’s worries were palpable. He had seen the Butterfly sisters, Kanae and Shinobu, grow from spirited children into formidable warriors. Kanae, the elder, was known for her serenity, but beneath her calm exterior lay a will of iron. She had clashed with Shinobu over countless issues, from the treatment of demons to the adoption of Kanao. Now, she sought to use this moment to impress upon Shinobu the gravity of her recklessness. He glanced at the young hashira, looking for her protest but he met clear eyes.
Shinobu pressed her forehead to the cold, hard cobblestones. The rough surface dug into her skin, grounding her as she faced the consequences of her actions. “Oyakata-sama,” she began, her voice steady despite the weight of her admission, “nee-san is right. I take full responsibility for my actions. I will accept whatever punishment you and nee-san deem fit.”
Kanae bowed to their leader, and returned her gaze to her younger sister, her expression a mix of anger and concern. The Ubuyashiki garden surrounded them, its tranquillity at odds with the tension in the air. Kanae selected a slender stick of bamboo, its green surface polished by years of rain and sun. It was never meant for punishment, but it was the best they had.
She held the bamboo in her sword hand, swishing it through the air to test its flexibility. Kanae didn’t want to do this to Shinobu, but her sister had crossed a line—a dangerous path toward self-destruction. Fear fueled rage within Kanae. The easygoing hashira was infuriated, wanting to beat some sense into her stubborn sibling.
Kanae’s voice echoed in the quiet garden. “Insect hashira, Kochou Shinobu. You disobey Oyakata-sama, sheltered a demon and violated the most important rule in the Corps, stole Nezuko serum for the Corps, disregarded your own safety, plotted for suicide. Twenty strokes of cane for each offence would be appropriate. As your Shihan, I will administer them myself,” Kanae took a deep breath, ignoring the shocked inhalations of the hashiras. A hundred and twenty strokes of the cane were excessive, not to mention it would be delivered by a hashira. Never had members of the Demon Slayer Corps received such harsh punishment. Oyakata-sama had always forgave offences acted out of compassion, or vengeance considering the hurtful background of most members. The Insect hashira was the tiniest, the second youngest in the team. It was a guarantee that she would not be able to walk for days, and unable to fight for months. The punishment for escaping from a fight with demon was even lesser. Kanae remained stoic. “You can scream and cry. I only have one demand: don’t hide, and don’t try to block it with your hands, or else I may miss.”
As always, the impulsive wind hashira was the first to respond. “Kanae, Shinobu just made a mistake…”
“Mr Shinazugawa,” Kanae’s voice was cold, filled with indignation. Sanemi should understand her plan. “I am sure you’ll do the same to Genya.”
The wind hashira shut his mouth with the mention of his brother. Oyakata-sama looked at the tiny hashira with worries, his glances a subtle permission for Shinobu to disagree with the unusually harsh discipline.
“I’ll accept it.” Shinobu braced herself, her eyes shut tight, her clenched fists held rigidly at her sides. The bamboo cane descended, its sound sharp against the silence. The first strike left a crimson line on her white pants, and Shinobu’s breath hitched. Blood drained from her face. She hadn’t anticipated this level of pain. She stumbled forward, but quickly supported herself with her forearms and resumed her position.
“These twenty strokes,” Kanae declared, her voice unwavering, “are for your disobedience to Oyakata-sama.”
The second strike followed, and Shinobu stumbled again. The hashiras watched, their collective breaths held. Shinobu’s resolve remained unbroken, even as the bamboo left its mark.
As a hashira, Shinobu understood the strength of her fellow swordsmen. They could behead demons with mere arm strength. But this—this was different. Kanae was the flower hashira, the one who had fought Uppermoon Two for an entire night, slaying countless demons. Shinobu’s teeth gritted together, and she swallowed her sobs. She deserved this punishment.
The bamboo struck again, and again with jaw-rattling force. Each stroke seared through her and burned her buttocks like hot iron, but Shinobu refused to cry out. She would bear this pain, not just for her own sake, but for her sister. Her sister’s anger was justified, and Shinobu accepted it as penance.
“These twenty are for your violation of the Corps’ code: sheltering a demon.” Again, the cane bit into the flesh of her behind, a testament to the gravity of the offence
Kanae’s emotions are a tempest within her. As she lowers the bamboo cane, its sharp impact echoing through the garden, she feels a mixture of anger, sorrow, and determination. The weight of her responsibility as the flower hashira presses down on her shoulders. She didn’t want to hurt her sister, but Shinobu’s actions had forced her hand.
Deep down she understood that her rage was fueled by fear—the fear of losing Shinobu, the fear of the Corps crumbling under the weight of disobedience. She knows the consequences of leniency, the fragility of their existence in a world overrun by demons.
“These twenty are for your crime of stealing Nezuko serum from the Corps.” The only answer to Kanae’s accusation was the thunderous crack of bamboo against soaked fabrics. Shinobu’s pants were a canva of scarlet lines. There was no doubt that the skin under her thin kimono was far worse that what other hashira imagined. Her silly sister was forcing herself to not cry out.
Showing weakness wasn’t weak. Kanae’s heart aches for her sister’s resilience, but she needed to wake Shinobu from her reckless loop of taking everything on her shoulder. Kanae’s gaze remains fixed on Shinobu’s trembling form. She doesn’t want to break her sister; she wants to save her. But her sister was too stubborn to be convinced. She gritted her teeth, her sword hand steady, and delivered a particularly harsh stroke to the younger hashira’s sit spots, earning a faint, strangled scream.
Sinobu’s vision blurred, her tears a result of her embarrassment of being disciplined in front of her fellows, and her ashamed of not considering her fellows in the Corps when reviving Kanae. She admitted that she prioritised her sister over everything, including her own life, and she never regretted reviving Kanae. The physical pain was a price she was willing to pay for her sister.
With every thud of the bamboo, a jolt of pain surged through her body. She was no stranger to wounds and cuts as a demon slayer, but being beaten in her buttocks felt far worse than being scratched by a demon's claw. Humiliatingly painful. Her lower body went ablaze and the pants provided no protection to the cruel instrument. Shinobu bit her lips to remind herself to stay awake, but the edge of her vision slowly faded.
“Flower hashira-sama, please stop. Shinobu-chan has passed out!” a concerned Mitsuri intervened. Kanae muttered a weary smile to comfort her, but didn’t let go of the slightly splintered bamboo.
Kanae eyed Shinobu’s pale, petite body. Silent tears mingled with sweat, her hairs stuck to her cheeks like she had been thrown into water. White marks appeared from biting her own lips and drugging her nails into her fists. Kanae flinched when she put her attention on Shinobu’s backside. Scarlet marks marred her buttocks and extended to her upper thighs. She could almost see the purple bruises on her hips through her sweat soaked pants. She sighed, making use of her skill as a healer, she pressed on Shinobu's philtrum and forcefully aroused her. Her voice softened to a tired whisper. “Shinobu, get on the bench.”
Her younger sister pushed herself up, but her legs wavered. Kanae grabbed her elbow and pushed her onto the bench effortlessly. The straddling position, though humiliating, was a leniency to the punished hashira as it allowed her to rest her body and prevented her from clenching her gluteus. Kanae knew it caused far more damage to tensed muscles than to relaxed flesh, especially when her sister was slim. She patted her sister's sweat soaked hair like she used to do when they were young. “Grab the bench. Halfway down, Shinobu.”
Shinobu's composure broke due to the deep affection she heard in her sister’s voice. Her tears ran freely and she choked out loud, wet sobs like a small kid reprimanded by her parents. Oyakata-sama winced at the heart wrenching cries of his child. Shinobu was one of the toughest hashira of the Corps. Despite the death of her parents, the death of her sister and the death of her numerous portegee, Shinobu had always been calm and mature, maintaining her kind smile and gentle tone no matter how bad the situation was. As compared to Kanae’s unconditional optimism, Shinobu was realistic and acted more like the elder sister in the butterfly siblings. Oyakata-sama had seldom seen Shinobu cry, and he sometimes forgot that Shinobu was barely an adult, and she had bared far too much at her age. “Kanae…”
“The rest are my punishment to you as your Shihan and your nee-san,” the former flower hashira declared. “To me, nothing is worth more than your life, your health and your well-being. Exchanging your life for mine was unwise, avenging me at the expense of your life was foolish! You promised me not to be reckless!”
Kanae landed relentless strokes to her sister's buttocks, but Oyakata-sama could sense Kanae's clemency. Though the tempo was frightening, she aimed most of her strokes on Shinobu's lower buttocks, the fleshiest part with more protection of fat. The cane striked upward, rippling the flesh instead of biting deep into the muscles.
As a healer herself, Shinobu understood the theories and knew that the continuation of the punishment was necessary. Rules were rules. Her defiance must never go unpunished, even if she was a hashira, especially when she was a hashira. An example had to be set. Yet, all cells in her body rebelled against the idea of taking more strokes. She forced herself to go limp and accepted them but she could not stop herself from trying to reach back. Kanae spotted that before she humiliated herself by covering her bottom and pinned her arms on her lower back, continuing the assault. With a closer distance, the hits were more bearable but each stroke further opened up her previous cuts, the impact radiating to her bruised muscles. Her thighs twitched in their own accords, each strike resulting in a bounce of her legs. She howled into the wooden bench, chest heaving with sobs and intangible pleas.
Kanae quickened her pace, each stroke a whooshy snake bite to her sister’s behind. She was sure there was no intact skin beneath the fabric, but she held the bamboo high and wielded the cane, making sure the Kakushi and the swordsman outside the wall could hear the result of the transgression.
The final strokes were a crescendo of agony. Shinobu nearly suffocated from her own sobs, her cries hoarse and her body convulsed with the pain. Kanae's throat felt tight. She dropped the long splintered bamboo. The dark red stick fell on the cobblestone with a thud. “It’s over, Shinobu.”
The young hashira took a moment to catch her breath and pushed herself up with her forearms, wincing as her bottom was stretched. She pressed her forehead to the bench, “Thank you for your punishment, Oyakata-sama.” but she would not promise to not do it again.
“Kakusi, please escort Insect Shinobu to Butterfly Mansion,” Kanae didn’t meet her sister’s gaze of indignance and ignore her protest to walk herself out of the Mansion. “Oyakata-sama, my sister would not be able to use her breathing style and handle her duties as a hashira in the near future. May I beg for your generosity to free her of the responsibilities when she is recovering? I, as a former hashira, would take her duties.”
************
With her drained body, Kanae stepped into the Mansion with a heavy heart.
“It is unfair!” Aoi Kanzaki’s voice cut through the air, sharp and desperate. “Shinobu nee-san had contributed so much to the Corps. She might have been wrong this time, but no one was hurt in the end. She saved the flower hashira!” Her frustration reverberated off the walls of the Butterfly Mansion, shaking the delicate paper screens.
Kanae paused, leaning against the wooden frame. She had seen the aftermath—the blood-soaked fabrics, the raw wounds that marred Shinobu’s once flawless skin. The punishment had been severe, administered by their leader, Oyakata-sama, and the other hashira. Kanae clenched her fists, torn between loyalty and compassion.
“Aoi… it’s okay,” Shinobu whispered, her voice barely audible. Her eyes, usually cheerful and soothing, now held vulnerability. “I’m okay.”
But Aoi wouldn’t be pacified. “Nee-san! Look at yourself!” Her frustration spilled over, and Kanao winced as Aoi’s anger surged. Kanao, ever dutiful, tried to peel off Shinobu’s blood-soaked pants, but the fabric clung stubbornly. Aoi’s command cut through the tension. “Kanao-chan, it is useless. You need a pair of scissors—yes, the red ones. Cut her pants off.”
Kanao hesitated, her trembling hands hovering over the fabric. She glanced at Shinobu, who lay there, pale and fragile. The great master of the Butterfly Mansion, reduced to a trembling and moaning patient on her bed. The oldest butterfly girl revealed Shinobu’s sweaty back and placed a cool towel on her lower spine. Her voice softened, a rare tenderness. “Nee-san, the fabric sticks, and I have to cut it off. It will hurt a little.”
With precision, Aoi snipped the kimono, revealing the angry welts and jagged cuts. Kanao’s breath hitched. Her sister hid her tears and moans in the pillow, but pain etched on her trembling form was unbearable. Her sister had endured so much throughout the years. Kanao held Shinobu’s hands, her own tears blurring her vision that she almost missed the slim figure entering the room.
Kanae shuffled to Shinobu’s side with anxious steps. She doubted if her sister resented her for the usually harsh discipline that she had delivered. The cane had splintered, leaving its mark. She didn’t need to look to see the aftermath — she heard Shinobu’s cries of agony and felt her bottom break under her strength.
Shinobu’s pained moan startled Kanae and dragged her out of her wandering thoughts. “Shinobu-nee-san, don’t clench your buttocks. I need to pluck the splinters out before cleansing your wound. I cannot do it if you are clenching them!” Aoi was exasperated. She understood that it was a natural muscle response from pain. Her frustration was directed inward, rather than toward her sister.
Without saying a word, Kanae sat on the edge of the bed, and lifted Shinobu gently onto her lap. As the second-best healer in the Butterfly Mansion, she knew more anatomy than other butterfly girls. She lifted a knee to support Shinobu’s stomach.
“Nee-san!” Shinobu had full realisation of what her sister was going to do. Her face blushed in a tizzy and she tried to push herself up when her stomach hit a pair of knees. Being caned in such place in public and baring her buttocks in front of her younger sisters was humiliating enough. Yet, her sister was far stronger and she was trapped. She buried herself in her pillow, accepting her fate.
The younger butterfly girls didn’t know the implication of Kanae’s gesture. The former flower hashira stabilised Shinobu’s hip with one hand, and gently lowered her other hand between Shinobu’s thighs, using her thumb to apply gentle pressure to her anus and draw a line down her perineum.
Shinobu shivered uncomfortably when her most sensitive part was touched, reflexively relaxing her gluteus and spreading her legs. Aoi took the chance to remove the splinters in the battered flesh, but Shinbo would rather they stay in her body. The oldest butterfly girl was glad that her sister forgot the pain for a moment. She professionally proceeded, grabbing a few alcohol-soaked cottons and cleaning the flesh with careful tweezers. The butterfly girl was met with violent struggles when the cotton touched the open flesh, but Kanae held Shinobu down with one hand when continuing to force Shinobu to relax with the finger on the younger girl's perineum. The Insect hashira shivered with pain, and cried with all her strength and tried to wriggle her way out. Her howls were unable to be contained by the pillow she used for her dignity when Aoi started to carefully clean the lower parts of her butt cheeks, where her buttocks met thighs, and where she had taken the most beating. The cuts there were deep and Shinobu felt like Aoi was peeling her skin from her flesh.
Shinobu clawed her mattress helplessly and whimpered to the pillow. Kanae couldn’t stand watching her sister to relive that pain. She covered Shinobu’s face with a bag of sedating herbs, easing her into sleep. Shinobu's breathing steadied, and Kanae brushed a strand of hair from he's younger sister's forehead. “You've endured so much, my sister,” she cooed. “Sleep, Shinobu. There will be no pain in your dream.”
Aoi was weeping silently, her tears a protest to the mistreat her sister had endured, but she dutifully switched to apply the ointment to Shinobu. Kanae moved her sight from Shinobu’s battered backside, her thighs twitching even in her sleep, and met Kanao’s teary, blaming gaze. “Kanao, are you wondering why I did this to Shinobu?”
The young protegee nodded, her eyes never leaving Kanae and Shinobu. Kanae smiled bitterly, "This is the only way to stop Shinobu from fighting a demon far stronger than her research, and her anticipation. Shinobu is the toughest person I’ve seen, the most stubborn I’ve seen. She wouldn’t give up her vendetta against Douma if she could walk.”
“She would use all her means to find Douma and kill him, even if this means sacrificing her own life. She poisoned herself, Kanao. Aoi must’ve known by now while tending to her wounds,” Kanae caressed Shinobu’s cheek and tried to soften her frown. “She had protected all of us for so long at the expense of her own, but the silly girl doesn’t know how precious she is. I am going to stop her from hurting herself, even if she resents me. Shinobu is too important to me, and I am sure, to you all.”