Written for the HitsuKarin 2015 Valentine's Day Challenge.

"Really," Karin drawls, resting her face in her hand, completely sceptical, first glancing at her classmate who's now fuming because evidently she hadn't meant to shout that loudly at her friend, then Karin slides her gaze at Toushirou. "Cutest guy in our grade. You?"

"It's tough being me," Toushirou shrugs, looking modest and smug, and Karin rolls her eyes, while he starts eating lunch.

"It's tough being cute, you mean," Karin snorts. He isn't. He totally isn't. Karin's known him for a good four years and cute isn't the right word to describe him. Sometimes it's asshole, and sometimes it's oblivious idiot, and sometimes it's something else entirely. It's always an insult as a term of endearment. "The cutest, in fact."

Toushirou sighs heavily. "The daily struggle of any ordinary teenage boy."

The sarcasm is strong today.

"I bet," Karin agrees too easily, then adds as an afterthought, "With the age appropriate angst of dreaming that one day he'll become tall, of course."

One of the things Karin loves about herself is that she's taller than him by centimetres.

"It'll happen," Toushirou vows. He lowers his voice so it almost becomes a growl; music to Karin's ears. He narrows his eyes at her, while Karin slurps the last drops of her juice box noisily. "Just you wait."

"I don't know," Karin hums, disbelief practised too easily on her face as she brings up old arguments back to life just for the sake of annoying him and taking him down a peg. "You know what they say, all that fighting, all that paperwork, all that homework—"

"What are you trying to say?" Toushirou glares, officially growling. He knows exactly what Karin's trying to say.

Karin grins, feeling like a fiend. "Nothing. I'm just wondering, if you spend so much time doing all those stressful, tiring activities, how on earth are you going have some energy left to grow?"

"I'll make it happen. Shut up," Toushirou's voice rings true with determination and it's a delight to watch every single time Karin infuriates him for the hell of it.

Score one for Karin.

After a while, she asks, "Girlfriend, huh?"

"The cutest guy has got to have the cutest girl, right?" Toushirou deadpans, smirking just a little.

"Oh really," Karin says, stretching both words as much as she can, before quickly demanding, "Who is she?"

It's a mistake the second she says it.

"Why, Karin," Toushirou turns sly and a good word to describe him now is piece of shit. Karin's ears a burning. She hopes it doesn't spread to the rest of her face. "Jealous?"

"As if," Karin scowls, squirming. It's too late, she can feel blood rush to her cheeks.

"Karin."

"Well," Karin shrugs, her face officially on fire. She coughs. "Maybe."

He looks stupidly pleased, and Karin's heart is going to burst. Her stupid heart. His stupid face. She doesn't know which she wants to punch more. She thought she'd been so good at keeping her pining a secret. At least, from him. If not, the entire world.

"What if I told her that my girlfriend was you?" Toushirou asks, eyes shining and so very green.

"Why, you asking?" Karin snaps back, mouth moving before the words properly register and her heart stutters stupidly in her chest and happiness trembles in her hands. Her eyes widen.

"Well," Toushirou shrugs, his cheeks turned pinkish. He coughs. "Maybe."

She doesn't know whether to punch him or kiss him. Possibly both.

"Then ask," Karin says, and her heart restarts again, as he grins with a stupidly flirtatious grin. Score one for Toushirou.

"Karin, would you be my girlfriend?" Toushirou asks, tilting his head slightly, the first time in his life acting cute and Karin doesn't know what to do except say yes with a vigorous nod.

"Cutest guy in our grade, huh," Karin repeats later, when they walk to her house together, hand in hand. Yuzu's going to be ecstatic. But she's only going to be told that after she's had her chicken soup. It's good for the soul.

"He happens to be dating the cutest girl," Toushirou smirks, overbearingly satisfied with himself, and Karin can't fault him for his impeccable taste. Their intertwined fingers swing lazily back and forth.

"We'll see how long that sweet-talking lasts," Karin laughs, cheeks glowing warmth, "it'll turn into fighting talk soon enough. I'm still going to wipe the floor with you when we play Tekken."

"Bring it on, Kurosaki."