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Say You'll Always Be Mine

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Sanemi has always been closer to Genya than their other siblings. After their mother and siblings were killed by their father in a fit of drunken alpha rage, Sanemi became even more protective of Genya. Sanemi was content for their world to only consist of themselves, but then Genya met them, the Kamado siblings and their annoying friends. Now, Genya insisted on spending time with them, cutting into Sanemi’s time with him!  

 “Ne, Sanemi-kun, don’t you think this is kind of creepy?” Shinobu asks Sanemi, who is currently hiding in a bush watching his precious brother hang out with some fucking annoying brats

 “It’s not creepy, I’m just making sure he’s safe!” Sanemi hisses back. Kamado Tanjirou may have the rest of the world fooled with his smile and easygoing nature, but Sanemi’s not a fucking dumbass. Genya can be dense and easily taken advantage of! Even if Tanjirou is already in a committed relationship with an obnoxious alpha named Ino-something and some teary eyed beta. Nezuko is just as bad as her brother- totally unphased by Sanemi’s yelling to stay the fuck away from Genya.

 “No, it’s definitely creepy,” Muichirou deadpans. Sanemi wants to strangle Muichirou, but reminds himself that he can’t keep an eye on Genya if he’s in jail. Sanemi settles for glaring at Muichirou instead.

 “What the fuck are you doing here?!” Sanemi grits out. If Muichirou and Shinobu are here, then that means Mitsu-

 “Eh? Sanemi-kun, what are you doin- oh it’s Genya-kun!” Sure enough, Mitsuri has arrived with Iguro. 

 “He’s most likely partaking in some kind of disgusting behavior Kanroji-san,” Iguro responds.

 “Give him a break, if I had a cute omega like Genya I’d wanna see him every chance I got, and then I’d fu-“ Before Uzui can finish his sentence Sanemi tackles him.


 “Sanemi, please refrain from injuring Tengen. I won’t have the both of you brawling in the streets.”

 Sanemi immediately leaps off Uzui and bows to the newcomer.

 “Forgive me Ubuyashiki-buchou. Uzui said some inappropriate things about my younger brother, and I lost my temper.”

 “Speaking of Genya-kun, where is he?” Shinobu asks. Sanemi whips his head around only to find that Genya and his friends have disappeared. He begins to panic; he’d been so focused on beating up Tengen, he’d lost sight of Genya.

 “I asked Kyoujurou to take them to go buy some sweets from the store over there.” Ubuyashiki explains before Sanemi can work himself into a frenzy. “I’m sure Kyoujurou and Gyomei are more than capable of keeping them safe.”

 “Ah! I want sweets too!” Mitsuri pouts.

 “I’ll go buy one of everything for you.” Iguro volunteers.

 “There’s no need Iguro, I’ve instructed Kyoujurou to buy enough for everyone. It looks like they’ve finished. Let’s all move over there.” Ubuyashiki points to a long rectangular table in the park. Sanemi glares af Uzui one last time before heading to the table to secure a spot for himself and Genya. 

 “Nii-chan! I picked out some daifuku for you!” Genya happily sits down next to Sanemi. “They had watermelon ice cream too!” Instantly, Sanemi feels calmer with Genya by his side. Sure, Tanjirou and his boyfriends ended up across from them, but Genya was leaning against him and his scent was soothing.

 “Oi Tomioka! Let’s fight!” Inosuke shouts when Giyuu arrives. Giyuu ignores Inosuke and nods at Tanjirou before sitting beside Shinobu.

 “Ubuyashiki-buchou, the arrangements have been made for tomorrow.” Giyuu announces as he reaches into a bag, looking for a snack.

 “Shinobu-nee, you have practice tomorrow?” Aoi asks. Genya turns to Sanemi and frowns.

 “Nii-chan, you said we would go to the store together tomorrow…” Sanemi immediately feels awful upon seeing Genya’s pout. He does recall promising Genya to take him to the nesting supply store, but he can’t refuse a request from Ubuyashiki. Not after all that Ubuyashiki has done for them. 

 “How about we take all of them with us, Ubuyashiki-buchou?” Rengoku suggests. “I’m sure it would be fun and beneficial to them to see us train.”

 “That sounds like a terrible idea. They’ll be nothing more than a distraction. These brats are too low level to even comprehend our training.” Iguro snaps.

 “Oi! Let me show you how low level you are compared to me, the great Inosuke!” Tanjirou and Zenitsu both grab on to Inosuke to prevent him from jumping on the table. Sanemi sees Genya hunch next to him at Iguro’s words. Sanemi wonders if cutting out Iguro’s tongue would put Genya at ease again.

 “Oh, that’s too bad. Mitsuri-chan and I bought swimsuits in case we had free time after training.” Shinobu sighs. Iguro immediately turns to her with interest.

 “Yeah! It’d be so fun for us to stay for a few days with everyone! I want to swim! We could have a barbecue too!” Mitsuri adds wistfully. 

 “But if Iguro-kun is set on focusing on training, we can always arrange for a trip to the beach without him, right Mitsuri-chan?” Shinobu smirks. Hook, line, and sinker.

 “Ubayashiki-buchou, I was too hasty. We should take this opportunity to strengthen our bonds as a team and allow the next generation to observe what will be expected of them,” Iguro pleads with Ubuyashiki. Sanemi snorts at how easy Iguro is. 

 “Very well, does anyone object to this plan?” Ubuyashiki asks. When no one disagrees, Ubayashiki nods and motions to Himejima. “Please contact the house and have them prepare extra futons. I hope you all don’t mind sharing rooms.” 

 “It’ll be like a sleepover! I’m so excited!” Mitsuri squeals. She starts to chatter and make plans with Aoi and Shinobu as Nezuko and Kanao listen. “Does everyone have a swimsuit? We should bring our yukatas too!” 

 “Looks like all the girls will be fine rooming together. They can have the largest room then.The beach house has an additional 4 rooms for us to divide amongst ourselves and a master suite for the captain.” Himejima explains. Iguro looks disgruntled as the prospect of having to room with another while Giyuu looks indifferent. 

 “Genya! Let’s all room together and have a sleepover too!” Tanjirou announces excitedly. “Tokitou-san! You should join as well!” Sanemi’s vision goes white with rage for a moment.

 “Fuck no. Genya is staying with me and no one else,” Sanemi snarls. Tanjirou tilts his head in thought before turning to Genya.

 “Who do you want to sleep with, Genya?” Suddenly all eyes are on Genya with interest. Sanemi scowls at all the attention on his brother, but also waits to hear Genya’s answer. 

 “Ah… Well, I’d like to stay with…” Genya stammers. He begins to blush and turn red, his eyes dropping down to his cup of ice cream.

 “Don’t worry about your brother, just answer the question honestly, Genya-kun,” Shinobu smiles reassuringly. 

 “I’ve never been to a sleepover before…” Genya mumbles. “But, I haven’t slept with aniki in a long time,” he adds as an afterthought.

 “Poor Genya-kun. Big bro Sanemi not taking good care of you? I’ll keep you company at night…” Uzui winks. The table creaks with the force Sanemi grips it with as he reminds himself not to strangle Uzui.

 “I’ve heard that pack activities have a positive impact on the health of an omega,” Aoi mused. Tanjirou nods and fixes his best puppy dog eyes at Genya.

 “Or are you too scared to face the great Inosuke-sama in a pillow fight?” Inosuke challenges. Genya forgets the attention on him and turns to Inosuke.

 “I’ll show you who’s stronger!” Sanemi wants to face palm with how easily his brother rose to the bait, but settles for plotting ways to end Inosuke. 

 “What about you, Tokitou-san?” Tanjirou asks. Muichiro appears to mull it over before nodding.  

 “Listen up brats, if anything, and I mean anything happens to Genya, I’ll personally chop you all to pieces and feed you to the birds.” Sanemi threatens.

“But aniki…” Genya starts, but Sanemi interrupts him.

 “No buts. We’ve wasted enough time here, let’s go home Genya,” Sanemi stands up and grabs Genya’s arm to drag him away. Sanemi’s not sure how much longer he can tolerate the others. 

 “You didn’t even decide who you were going to room with Sanemi-kun!” Mitsuri shouts after him, but Sanemi’s done listening for the day. When they get far enough where Sanemi feels he can somewhat relax again, he relaxes his grip on Genya. 

 “Nii-chan, if it bothers you that much, I’ll stay with you.” Now, Sanemi feels like a dick. His instincts scream for him to keep Genya with him at all times, but the Shinobu’s sister is right - pack activities are important. 

 “It’s whatever. I’ll kill anyone who bothers you.” Genya still looks unsure at Sanemi’s reply, but they’ve arrived home. “I’ll make dinner, go wash up first.” Genya hastens to obey his brother and scampers into the house. Sanemi sighs as he opens the fridge to start preparing dinner. He’ll have to pack for them tonight.

 Message from Giyuu

 <<You’re staying with me and Rengoku.>>

 Good, better Giyuu and Rengoku than fucking Uzui and Iguro. Sanemi silently prayed for Himejiwa.