Both of you were patrolling together in the city, chasing a couple of troublemakers who were rioting, it didn't take long for you both to catch them and it didn't take long for a good amount of crowd to come to congratulate you and thank you. And although Katsuki wanted to appear disinterested he enjoyed the attention and praise.

As he dragged the criminals with the police he noticed that you weren't in sight, there were a lot of people around, which disconcerted him, he abandoned the troublemakers and walked abruptly through the crowd to find you, starting to get irritated at not being able to see you among the crowd of people.

He pushed a few until he finally managed to see you, at this point he was already quite pissed off and when he found you with your back turned doing who knows what he stretched out his arm and pulled your hair to get your attention

"Hey moron! What the hell are you doing!? Why are you getting away like that?"

He snapped as he looked at you with a frown not caring much about the crowd around