drama from my school

this guy, lets call him "B". I got spacehey to write out drama so other can see. B touched me without my consent and called himself a "good doggy" and lies about having depression and abt his mom being dead, and i cut ties with him. then after a while he then went onto my pinterest and talked to my online friend through there and told my online friend things abt me and said "well ig ill go die now bye" making my online friend worried thinking they caused this for some reason. My friend, who is his ex gf and i yelled at him. I didn't talk to B for more than 6 months but i heard him lying abt having cancer and soo much more, then just in recently he talks to me like we're friends and pretends everything is okay, I only respond to what he says and asks to me. A few days later when he started talking to me, he was talking to someone and was like "well lettuce hated my guts, like she HATED me idk why, idk what happened ig we're friends now" i looked at him and said aloud that I still despise him and we're not friends. And again, after that he still tries to talk to me, I still answer. Today, I was eating my lunch in the classroom and he started making comments on how he's going to khs and acting like the victim when he really isn't, my friend got worried lets call him K and my other friend didn't care his name is C. K kept comforting B, I wasn't aware of what was happening because I was drawing and was distracted, we were all at the same table. My friend C was telling him "dude stfu no one cares, stop lying abt shit like this. it isn't cool" B got all pissed off at C because C wasn't comforting him, so he put his head down and said "I'm going to sleep" My friends and I were passing notes, because K felt bad and thought it was his fault. My friend and I we're telling him it isn't and he lies abt doing this type of stuff a lot. K calmed down, then B put his head up and said "I had a dream where, Lettuce and C were insulting me and I was crying..K was laughing at me". We started to laugh, because we found it funny. My friend C started yelling at him telling him to stop acting like the victim and stop doing this and that, he couldn't continue what he was going to say because we were going to leave. When we were leaving the class my friend (her name also starts with a C so we'll call her CC), So, I told CC about B's stupid dream, nad B heard me so he waved at my friend so I don't tell her(?) I don't know how that stops me from doing anything, but she told me that she told B's brother abt this and to please do something about him because it is getting out of hand. I told her thanks, and that's about it. he's pretty much just a liar who does things for attention.