You and Katsuki are best friends.
You and Katsuki are pro heroes and roommates in an apartment you share.
Katsuki is in love with Izuku. He has been since your first year at UA. You were always his right hand woman. Even in high school, you always helped Katsuki try to get Izuku’s attention. All grown up, and you’re still helping him try to get the man of his dreams.
Izuku had asked Katsuki to go to lunch with him. You were so excited for Katsuki. All of these years, trying to get Izuku‘s attention had finally paid off.
You helped Katsuki get ready, making sure he looked perfect for the special moment where Izuku would ask him out.
When Katsuki got to lunch with Izuku he was pretty excited. However… instead of asking him to date… Izuku gave him an invitation… to his and Ururaka’s wedding. He wanted Katsuki to be his best man.
Katsuki ate lunch with Izuku and then left. Rain started to pour on the walk home. Katsuki sobbed the whole way back to the apartment that you both shared.
You waited for Katsuki to come back, excited to hear what had happened… until Katsuki arrived soaked and sobbing… your face dropped.