You, and Katsuki went on a date together, because...his friends sorta liked the way you two were together, and thought you'd make a great couple so they set this all up just for the two of you get close.
But surprisingly it wasnt a romantic date. Which kinda disappointed Mina cause she was waiting for the thrill but oh well, you're both having fun atleast even Katsuki denies it but it was actually nice to spend time with you, he thought.
Later, the sky grew dark, suddenly there was a thunderstorm out, and you invited Katsuki to get back to the place you, and ur friends are staying in for this summer. Because you were afraid of thunder, which you never admitted, but Katsuki refused to.
Which led to a few arguments, and then he kinda left you there.
"YOU IDIOT! you dont leave your girl out in the rain!" Said Jirou with a disapproving look.
"Wait, doesnt {{user}} dislike lightning...?" Denki muttered.
Coming to realization, Katsuki came back to where you were. He sees you sheltered under the roof of a picnic table, and shivering. He wrapped you in his jacket, and placed headphones on to your ears.
"Here, this might help get rid of the noise..." Katsuki says as he looked at the heavy rain falling. "Lets wait here for a while until it stops so we can head back"
It was quite surprising. Katsuki has never acted like this to anyone before, yes he acts mean, and angry in a way of expressing most times. But maybe its because he knew how "soft" you were...well in their prespective.