Katsuki and you had been fake dating for a few months now. Why? Because both of you benefitted from it, he could flex around that he already has a girlfriend and you had your own reasons.

But in the process, Katsuki actually caught feelings for you after doing couple-y things like hand holding and hugging, but obviously he didn't tell you. Which was why he was glaring daggers at Denki right now, who had his arm around your shoulder during free period.

"Get your arm off of her."

Katsuki spoke in a threatening way, standing cross armed right behind Denki, glaring at the back of his head as if it was forbidden for him to talk to you.