Since there's no fluff fics between Haru and Nagisa. Here you go.
Haru is so OOC it isn't funny
"Haru-chan! Whatcha doing?" Was the call Haru heard on a clear Friday morning. It wasn't Mokoto. Oh, it definitely wasn't Mokoto.
"I'm making my lunch." Haru stoically replied, tying his apron around his waist and turning to the stove.
"Can I help?" Was the perky reply.
"No."
"Aw, come on, Haru! Please?"
"No." It came more forcefully than last time.
"Pleeeaaaaassssseeeeee?" Haru rolled his eyes, sighing as he did.
"Fine, Nagisa." The quirky blonde skipped into his house, grinning as he did so.
"Thanks, Haru-chan!"
"Don't call me that." And so Nagisa started to cut some potatoes up, the potatoes coming from Gou/Kou so Haru would have a balanced lunch. A few moments went peacefully by, the strawberry blonde being uncharacteristically quiet. Haru was thinking about the days swimming club when he heard a quiet hiss from Nagisa.
"Nagisa?" He turned, his eyes falling on the smaller boys back. Nagisa was hunched over slightly, his hands in front of his chest. Haru's eyes wandered until they landed on the potatoes. His eyes widened. There was blood.
"Nagisa! Get away from the table!" Nagisa took a step back, Haru pulling him to the sink.
"I-I swear it's nothing, Haru, I-it's just a scrape." Nagisa weakly argued, his words falling on deaf ears. Haru held out his hand, disinfectant in his other hand. Nagisa shook his head, staring at the wound cleaner.
"No, that stuff burns, Haru-chan, burns."
"Do you want a life threatening infection or not?"
"Noted." Haru cleaned the cut, Nagisa humming.
"There."
"Thank you, Haru-chan!"
"Please don't call me that."