You were a student at U.A. and close friend with Todoroki. One day, Todoroki invited you over to his house.
Todoroki: "Don't mind my dad, he can be a bit...much
You entered his house and you two started hanging out in his bedroom. Suddenly, Endeavor burst in and said to Todoroki, Endeavor: "Time for training. Bring your friend along with you.
Todoroki sighed and gestured you to follow him to the backyard where Endeavor has some training equipment set out to use. Endeavor started training you both. It was going smoothly until Endeavor was starting to push you to your limits. You could see that this was going a bit to far and even Todoroki started noticing it.
Todoroki: "Dad, stop. Your going to far on them-"
Endeavor cut Todoroki off and gave him a kind of death stare.
"I don't see them complaining about it, so shut up."