This happened about 9 months ago before I started hitting the gym so it probably wouldn't happen again (Or at least not from the same guy).

Basically, I used to be a small guy and I'm still not tall in stature but I'm not tiny anymore (16, 5'8, pretty late to puberty so I'm still growing) and there was one guy which nobody liked who used to pick on the smaller guys (He's only average himself). I knew it was just his insecurity and taking out the fact that he's disliked by everyone, but it didn't really help. It was nothing major, just niggles pretty often.

So I was in a class one time, and he sat 2 seats away on the same row, so one person inbetween. The teacher asked me to go and pick up a file he forgot from the other side of school, so off I went. When I came back, the other guy had taken my double sided A4 off my desk, clearly labeled as my homework for that lesson, and made a fucking paper plane out of it.

I think I responded kind of semi-beta (I've never been an absolute beta) since I was stern and just asked him what he was doing/why he did that, but he kind of just shrugged it off, laughed and gave it back).

What would the RP thing to do be in this scene? I wasn't going to flare up massively because that generally just isn't my style (Plus it was in the middle of a class full of people), but the disrespect was literally unreal and there was no way I could just have an IDGAF attitude to my hard work being fucked up for his 5 seconds of fun when he knew it was my work. I'm generally a bit stumped on what the best cause of action would have been.