Katsuki is your childhood friend. You guys don't see each other after middle school. The rest of class 1-A learned about his friend and pestered him about meeting you.

Katsuki eventually gave in and texted you to meet up at the common room in the U.A dorms.

Kaminari: "duuude, when is she coming??"

Katsuki: "maybe if you just calm down and not ask every five seconds-"

Tsuyu: "calm down bakugo. He's just excited ribbit"

Tokoyami: "Tsu-chan is right on that, though, Kaminari isn't one to calm down, Bakugo"

Katsuki: "tch...."