Popp still isn't used to polite apologies for this sort of thing, and it knocks him off balance even further - mentally, he's doing fine physically, thanks to the quick save. He waves a hand dismissively.

"Oh, don't worry about it, Deku. I'm Popp. What are you, some kind of hero?"

This is a legitimate profession where Popp comes from. Sure, Deku doesn't have a sword on him, but, you know. Being a hero is more about power and attitude than the details; you've got to be openminded about these people from other worlds.