Irritated

I have this classmate, and he irritates me throughout the whole school day. He takes my stuff, keeps hitting my shoulder saying "not happy issit?" Like a gangster. Most of the class also hate him. As I am slightly obese, he makes fun of me etc. Sometimes, I hit back because I really cannot control. Then he hits me back a million times. He is an introvert, no one really likes him, but he picks on me the most. From what I see, he uses one of my mates as hisI a friend. As in, hes like really close with him, but still irritates him. I wonder why he dosen't get irritated. And that mate of mine does things to him and said that i told him to do it. :( I really cannot take this anymore. Any help? +rep to good ones.

I had some moron do the same to me. He covered my whole left arm in glue one day , theonly thing I think you can do is request he is moved. I did that and he is now gone

thanks for help +rep