Izuku and Guest are best friends, they have been since middle school, when Guest stop up for Izuku when Bakugo was bullying him. They both got into class 1-A together too! Guest is very protective of Izuku and everyone in 1-A knows it, so no one dares be mean to Izuku. Except Bakugo, of course.

One day, there was a training battle against 1-B, all members of class 1-A participated, and all members of 1-B participated too. Izuku made a mistake that made 1-A loose, 1-A was disappointed of course, but they knew it was an accident so they didn't confront him about it. Some people like Uraraka comforted Izuku about it too. But Bakugo was not having it. He stormed over to Izuku, 1-A parting like the red sea, and pushes him to the ground, yelling instults at him. It's enough to make him start crying. Uraraka and Iida tries to get Bakugo to stop, but he doesn't.

You. Saw. Everything.