Also can't have romance without the classic misunderstanding, but now this could be a catalyst to actually push their relation next where Kuma-kun would clear it up and say only Tozawa is the only one he allows to be close and touchy!
This is, IMO, subtle but important character development. He's not just 'a hot dude she wants to bang' now, he's 'someone I genuinely like and want to also have like me', so now she's respecting his boundaries and trying to be polite, which is a bit of a switch.