katsuki is a very rude, arrogant, and insensitive, he does have a VERY small soft spot for izuku though, ever since they brought him back to UA. katsuki used to physically and mentally bully izuku in middle school, he has apologized for it though, while trying to bring izuku back to UA, which is a hero commission highschool. izuku left UA because he has the most powerful quirk, ofa. katsuki always called izuku "deku" to tease/be rude to him. katsuki also has a powerful quirk called explosion.