Chapter Text
Shinazugawa Sanemi paced circles around the Butterfly Mansion. Upper Moon Five and Four had been defeated. That’s good news, right?
But Genya was one of those slayers that defeated Upper Moon Four.
Sanemi did everything in his power to protect his baby brother. Even if it meant he didn’t get to be in his life, even if it meant acting like an asshole to drive him away. Just as long as Genya is alive.
But Genya still went out, became a demon slayer, and fought an Upper Moon. But Genya’s alive. That still doesn’t change the fact that his only baby brother left was trying to get himself killed.
He knew Genya was somewhere in the estate, getting recovered. All though, from what he heard from Shinobu, he didn’t really need to recover. When he asked her what she meant by that, she didn’t respond.
But it still lingered in his mind. Why doesn’t Genya need to recover?
He checked up on Genya but made sure he only did it when Genya was unconscious. He didn’t want Genya to think he was proud of him for trying to get himself killed.
Right now was one of those times.
He stopped at Genya’s door, technically Tanjiro’s room as well—but he was willing to ignore that brat whenever he came here—and peered inside.
Genya was sprawled out on the bed, hair messy and face filled with a soft smile. He looked peaceful in his unconscious state. A peace he should’ve been the one responsible for keeping. The peace he will be responsible for keeping.
Moments later, he made a decision. A heavy, binding sort of decision. All thoughts of allowing Genya space, to recover on his own, were gone. It was time to stop neglecting his brother’s safety as much as he was right now.
"You're not going anywhere," he muttered under his breath, a resolve solidifying in his throat. “I’ll take you home with me, how does that sound, baby… my baby.” He asked, knowing full well he wouldn’t give him another option.
He nudged Genya awake. When his brother groaned, eyes fluttering open, too dazed at first to grasp what was happening. Suddenly his eyes widened in surprise. “Sanemi?! What—What are you doing here?”
Sanemi had to pause for a moment. He didn’t like how Genya addressed him. “Sanemi?” What happened to “Nemi?” He’d have to make sure Genya would change that habit.
“Sanemi?” Genya whispered again, and Sanemi hated how scared Genya seemed to talk to him.
But here Genya was, given the chance to talk to his older brother. To tell him anything he wanted. “Sanemi, I’m… I’m sorry.”
“Excuse me?” Sanemi blinked.
“Sorry for saying such cruel things when you killed—” Genya hesitated. “When you protected me. I shouldn’t have called you a murderer—”
Sanemi remembered. He remembered how his heart had cracked each time Genya's words cut him to the core. It was a bitter memory, one that Sanemi held close even through the chaos shrouding them.
But…
“I don’t care.” Sanemi forced himself to push those memories away. All that he cared about right this moment was to keep Genya safe. Genya didn’t do anything wrong after all.
“What? B-but—”
“Shut it, Genya. Just… shut up for a minute.” Sanemi's voice was firm, leaving no room for argument. He stepped closer to the bed. “You’re coming with me. No ifs, ands, or buts.”
“Wait what?” Genya blinked sleepily, confusion and fear hazing his eyes. “But I’m fine, really! I just need to—”
“No,” Sanemi interrupted. “You’re not fine. You’re not going back out there. Never going to be a demon slayer, again. Not now. Not ever. I won’t let you.”
The younger Shinazugawa shifted uncomfortably. “Sanemi… you can’t ju—”
“Can’t just what?” Sanemi replied, crossing his arms as he leaned down closer to his brother, who was still trying to sit up. “Can’t just ignore how reckless you are? How many times you’ve put yourself in danger? You think you’re fine, Genya, but you’re not. That’s why I'm taking you home now.”
Genya’s eyes widened as he heard those words. Home? He should be happy to hear that. Home with Sanemi? But the look in Sanemi’s eyes made him feel… uneasy.
“I—I’ll think about it,” was the only response could muster.
“Think about it?” he hissed, his voice low. “You don’t get to think about anything. I’m not asking, Genya. I’m telling you. You’re coming with me, and that’s final.”
“Sanemi, please. You can’t just kidnap me. I’m a demon slayer too!”
A bittersweet sort of satisfaction twitched at the corners of Sanemi’s mouth. “You’re not being a demon slayer anymore. You’ll be my baby brother instead. I’m sure you can remember how amazing you are at that. That should be your job, worrying about being an amazing baby brother.”
“Sanemi, please…” he tried again, but it came out weaker than he intended. “You can’t—”
“Enough,” Sanemi snapped, grabbing Genya’s wrist and pulling him up into a sitting position, as gently as he could. “You think I’m going to let you go out and hurt yourself?”
Genya blinked, disoriented. “‘M not hurting myself—”
“You’ll be safe with me,” Sanemi continued, almost as if talking to himself more than to Genya. “I won’t let anyone even touch you. Not anymore. Not ever again.”
“Safe?” Genya echoed incredulously, “This is insane! I can’t just stay with you like a prisoner, Sanemi!”
“Prisoner?” Sanemi raised an eyebrow, a smirk cruelly plastered on his lips. “No way. You’ll be my little brother. I’ll keep you safe, warm, and where I can see you. And if that means keeping you in my sight at all times, then that’s what I’ll do.”
Before Genya could respond, Sanemi scooped him off the bed and into his arms effortlessly, despite Genya a most being 6 foot. The sudden shift made Genya gasp and clutch tightly to Sanemi's shoulders. “What the—Sanemi, put me down!”
“Nope.” Sanemi shifted him higher, ensuring Genya was safely nestled against his chest. Genya’s face was flushed, as it was both humiliating and comforting, feeling the familiar warmth of his brother so close. “You’re not walking anywhere until I say so. You’ll stay right here, where I can keep an eye on you.”
“Put me down!” Genya protested, squirming, but he felt the strength in Sanemi’s hold. His brother's grip was both possessive and protective
“Cute,” Sanemi commented dryly, completely unfazed by Genya’s struggles. “You think that’s going to work? Don’t you dare forget I’m a Hashira. I can deal with little brats like you.”
“Sanemi!” Genya shouted in frustration. “I’m not a brat—”
“I think you’re acting like one,” Sanemi shot back. “Brats like you need to be taken care of.”
“I… I’m a demon slayer too, not some weakling who needs to be taken care of…”
And then with a surprising twist of affection, he pressed a gentle kiss to Genya's forehead. “You’re not a demon slayer anymore, Genya. You’re just a baby brother who needs to be taken care of.”
It felt absurd to be handled like this, yet the warmth from Sanemi’s body was almost compelling. Almost. “You… you can’t just take me away! I have my own missions, my own life!”
“Not anymore,” Sanemi hissed. “Think about what you’ve been through. You think I’d let you go back into battle? You’re recovering, and you’ll stay with me until you’re completely better. No arguments.”
“I’m not recovering! I’m perfectly healthy now!”
“Yeah, right.”
Sanemi eventually brought them out of the Butterfly Mansion and his grip on Genya strengthened. “Hold on tight.”
Genya kicked and flailed in Sanemi’s arms, heart racing as they left the Butterfly Mansion behind. “Put me down! I swear I’ll knock you out!” he yelled, squirming furiously.
“Yeah? You think you can take me?” Sanemi challenged, a teasing smirk creeping onto his lips as he picked up the pace.
“Sanemi! I mean it! You’re going to regret this!”
“I’ve been regretting a lot of things since the day you decided to become a demon slayer,” he shot back, chuckling as Genya’s foot met his thigh in a kick that he barely felt.
“You’re just making this worse! Let me down!” Genya persisted, focusing all his energy into squirming out of his brother’s hold. He managed a strong punch to Sanemi’s shoulder, but Sanemi simply adjusted, his grip firm and loving.
If there was anything he wasn't going to allow, it was letting Genya go back out there to be a target.
With a final, desperate kick Genya managed to shift just enough to slip from Sanemi’s hold. Taking advantage of the chance, he fell down onto the ground, shuffling to his feet with a rush of adrenaline. Before Sanemi could react, Genya bolted away.
“Genya!” Sanemi shouted, taken by surprise. Dropping whatever gentle resolve he had for a moment, he chased after his brother. “Come back!”
Heart pounding, Genya raced through the massive forest, dodging trees as he desperately pursued freedom. The sound of Sanemi’s heavy footsteps grew closer, and Genya pushed himself harder, fueled by desperation.
“Since when did you get faster, huh?” Sanemi called out, his breath steady despite the urgency of the chase. “I remember when we were kids, playing tag, and I’d always best you.”
They tore past the entrance and into the deeper woods, Genya’s heart pounding a frantic rhythm against his ribcage.
With a swift motion, he lunged, catching Genya around the waist and lifting him once again.
“Got you!” Sanemi grinned, holding Genya tightly against his chest.
“No! Let me go!” Genya screamed, squirming in his brother’s iron grasp, but the more he fought, the stronger Sanemi held him. "Why are you doing this to me?!"
Sanemi sighed, in exasperation. “You’re unbelievable.” And without a moment of hesitation, he maneuvered Genya's body, positioning him so that he could use his haori.
Before Genya could even register what was happening, Sanemi swiftly wrapped the fabric around him, securing him into a tight bundle. “What are you—?!” Genya stammered, struggling against the snug restraints. “This is ridiculous!”
With Genya successfully tied up, Sanemi stepped back to observe his handiwork. “Perfect,” he muttered. “Now, no more running.” He turned away for a moment, attempting to catch his breath, but soon noticed Genya’s expression faltered, replaced by a deep sense of panic.
“Sanemi, please—” Genya whimpered, the fear in his voice trembling as he fought against the bonds. “I hate this! I hate it!”
Sanemi's heart dropped as he watched the tears well up in Genya’s eyes. It didn’t take long for the dam to burst; his brother broke into an uncontrollable sob, the sound raw and filled with confusion.
“Oh, God—” Sanemi started cursing under his breath, and his expression softened as he rushed back to Genya’s side. “Genya, hey, hey, it’s okay!” he said, paniking. “I’m here! You’re safe! You’ll be safe with me! Nemi will keep you safe!”
“I don’t want this! I don’t want to be treated like an infant or a prisoner!” Genya cried his voice breaking, fingers clawing at the restraints. “Please, stop it! Just let me go!”
Sanemi felt helpless; he had never seen Genya cry this bad, his cries penetrating through the very core of him. “Don’t cry, baby! I’m not going to hurt you!” He gently placed a hand on Genya’s shoulder, hoping to provide some comfort, but it only seemed to send Genya into another wave of distress.
“You don’t get it!” Genya half-shouted, half-sobbed. “I’m not a baby!”
Sanemi’s instincts kicked in, and he recalled what their mother used to do when one of her children was distressed. He grabbed Genya’s hand, squeezing it every couple moments, whispering soft, soothing words. “Shh, Genya, please calm down. It’s okay, Nemi’s gonna make it okay.”
In an attempt to calm him down, he shifted and pressed the heel of his hand against Genya’s neck. “You’re just… overwhelmed right now.” He applied pressure carefully, his heart racing as Genya gasped, the protests falling from his lips unsteadily.
Genya felt his body give in to the sensation, the world around him blurring as darkness enveloped him once more. “Sa…Nemi… I…”
Before he could finish that thought, Genya’s body slumped against Sanemi’s chest, unconscious.
He picked Genya back up into his arms, adjusting his grasp to make sure he was comfortable, despite being unconscious. As he started walking back toward his estate, Sanemi couldn’t shake the guilt that lodged in his throat. “I’m sorry,” he muttered softly, though he’d meant it for both of them.
Protecting Genya brought out the absolute worst in him—possessiveness that erupted in misguided actions, rather than the gentle brother he yearned to be.
When he finally reached the entrance to his estate, he carried Genya inside and took a quick glance around as he passed through the familiar halls.
Sanemi kicked the door to his room shut behind him, the soft sound echoing in the quiet space. He gently lowered Genya onto the bed, ensuring the younger Shinazugawa was laid out comfortably before he began to untie his haori from around Genya’s form.
“I’m sorry,” Sanemi murmured as he worked, his fingers loosening the cloth and smoothening it off his brother's body. “But I just can’t let you go out there again.” His heart ached at the thought of Genya facing danger, he was his older brother after all. He was supposed to keep him safe.
Once Genya was free from the fabric confines, Sanemi unbuckled the belts on his ankles—he knew it was a drastic measure, but he needed to ensure Genya wouldn’t be able to escape.
A mixture of guilt and determination coursed through him as he carefully tied the belt around Genya’s wrists and ankles, ensuring they weren’t too tight to hurt his baby brother but secure enough to keep him from slipping away.
“Just for tonight,” he whispered to himself, his voice barely above a breath. “Just until I figure things out, okay baby?”
Sanemi stepped back, glancing at Genya’s peaceful face but bound to the bed, the sight brought a complex mixture of relief and guilt flooding through him. Though he felt justified in his actions, the weight of the situation settled heavily upon his shoulders. He needed to ensure Genya was truly okay, not just physically but mentally as well. And that meant he would have to keep him comfortable and entertained until he accepted that maybe staying home with his brother wasn’t the worst idea.
With a sigh, he turned and left the room, deciding that a warm bowl of broth might ease Genya’s distress when he awoke. As he reached the kitchen, he reached for the ingredients there—the vegetables and herbs had an almost soothing aroma.
Pulling out a pot, Sanemi filled it with water and tossed in a handful of ingredients before placing it over the stove.
As the broth began to heat, he leaned against the countertop, pondering the conversation he desired to have with Genya later. “Maybe…” he whispered to himself, “if he has something warm in his belly, he might be a little more agreeable.” He chuckled softly, but the tightness in his chest remained.
No matter how far he pushed, he couldn’t escape the fear of losing his baby again.
He would do whatever it took to make sure he was safe—that was the responsibility of being an older brother.
With that, he settled down beside Genya, allowing himself a moment to breathe before settling in to watch over the younger Shinazugawa.
Samemi felt his eyelids grow heavy. It was not long before he succumbed to sleep, his body pulled to the warmth of his brother beside him.