Alright, so, Shouto had perhaps not considered all the possible consequences when he made the decision to put his sister and boyfriend in the same kitchen at the same time.
He’d honestly heard the words “your sister’s recipes” and mostly stopped listening because the thing was; Katsuki was a wonderful cook, amazing even. Shouto had struggled to fend off jealous, hungry classmates on more than one occasion and felt no pity when they lamented their failures.
Fuyumi was also a wonderful cook, and held the keys to some of Shouto’s most beloved childhood foods. There was, in his mind, no possible way that Katsuki learning her recipes could go wrong.
Shouto had made a crucial error.
He saw it now, far too late.
He had nearly forgotten, with how polite and slightly distant their relationship could be in its worst moments.
Fuyumi was an older sister.
Worse still, she had done a fair bit more raising Shouto than was reasonable for the years between them, after his mother was gone.
“So…” She began, after the quiet had gone slightly awkward by Shouto’s estimations.
Shouto shifted slightly on the stool he’d set up behind the counter, far from any accusations of being in the way but still well within sampling reach when the time came.
Katsuki grunted in acknowledgement as he tied an apron securely around his waist. Shouto had never considered the appeal of an apron before Katsuki. Though he was fairly certain the appeal was more Katsuki than it was anything strictly apron-related.
“Is there anything you’d like to start with?” Her smile was a little strained.
Katsuki answered in the negative which definitely meant that he fully intended to master all of her recipes so it didn’t really matter which one they started with.
Fuyumi hummed, looking through her book, and made an almost fond noise that really should have tipped Shouto off immediately.
“Oh, I have the marinade I used to help with for kabayaki in here.” She smiled and glanced over at Shouto. “Shouto was so cute back then. All proper and tiny.”
She leaned a little closer to Katsuki, like she was telling him a secret. “He wanted to get his words just right so it was ka-ba-ya-ki.” She enunciated carefully and slowly but just off enough that Shouto knew it was an imitation.
Katsuki huffed and some of the awkwardness Shouto hadn’t noticed at the start dissipated.
“You used to be so tiny.” Fuyumi mourned in his general direction. “Puffy baby cheeks and that devious little pout. I should track the pictures down while the meat soaks.”
Shouto felt it wise not to respond to that threat.
“Does he still do the pout?” She directed that at Katsuki as she moved towards the fridge. “I feel like he’s at that age where you’re the more likely target.”
Katsuki outright snorted at that and easily took the ingredients she handed him as he answered. “Does he?” Shouto loved that smile, it was gorgeous. “Let’s see…”
Nevermind, Shouto hated that smile.
“Well, I guess there was last week when he wanted kisses.” There was a pointed murmur about ‘pretty boy angst’ towards the end. Fuyumi stifled a noise behind her hand. “Or Tuesday, just sat there on the couch and looked at me with these sad eyes. As if I’m supposed to know what that means!?”
“Cold soba, he perfected that move when he was seven.” Fuyumi nodded sagely.
Shouto was a little offended by that comment, honestly, it did not take him a year to get right.
“Who has sad eyes they break out specifically for cold soba!?” Katsuki complained.
Fuyumi darted a pointed look in Shouto’s direction and Katsuki conceded with a grumble.
They worked quietly for a bit. Fuyumi was a good teacher, probably, Shouto wasn’t an expert. He was definitely supposed to have more faith in her skills but in his defense he’d never heard of elementary schools that gave students stove access. The initial awkwardness faded almost completely as they finished the marinade and Katsuki started to prepare the eel.
Shouto should have taken their growing comfort with each other as the warning it was.
“There.” Fuyumi nodded decisively as they placed the last piece of meat to soak for a few hours. “You know…” She started. “I never did get an answer out of Shouto. How did you two get together?”
“He didn’t tell you?” Katsuki smirked, outright smirked! Of course Shouto hadn’t told her! “Shouto.” He walked around the counter to casually lean on Shouto’s warm side. “Ran into a wall.”
“He what?” Fuyumi’s response was too startled to be called a laugh. Shouto was going to combust, possibly literally, and they were going to have to break out the first aid kit for his boyfriend.
“I was training.” Katsuki explained, seemed to remember the rest of the story and that he was telling Shouto’s sister about it, and the tips of his ears turned a bit pink. “It was hot out.”
Shouto leaned into his boyfriend and smiled, for one glorious moment completely unashamed of the incident. “Katsuki works really hard on his muscles.”
“Shut it.” Katsuki hissed.
Fuyumi couldn’t hold back the snort.
“I couldn’t take my eyes off him so…” Shouto trailed off. “I’m pretty sure he thought I was sick.”
“How was I supposed to know you weren’t delirious!?”
“I told him he looked great and he threatened to drag me to the nurse’s office.”
Katsuki’s ears were bright red now and Shouto decided he could be satisfied with his revenge.
“That’s how you started dating?” Fuyumi smiled.
“No.” Katsuki grumbled. “We didn’t start dating until the grand gesture.”
Shouto nodded, it had been very effective. “I made him his favorite meal and lit candles and clearly communicated my intentions.” He reported.
“For the last time, that was not my favorite meal, just cause you and Deku haven’t changed your favorite foods since the ripe old age of three does not mean I still think yakiniku and french fries are the height of culinary luxury.”
“Agree to disagree.” After all, they had each gotten a wonderful boyfriend out of it so really, he didn’t know what Katsuki was complaining about.