I don't understand this guy?

Okay so there's this guy and he acts like he likes me and then he doesn't. He makes fun of me in a playful but hurtful way all the time. Like for example last night i was texting him and he's complaining to me about one of my friends making fun of him, and i talked him through it and was like relax. And then when i said gtg byee, hes like by kobe. (He calls me "Kobe" like kobe bryant.. because i have a bigger nose) Like what the hell? He is a little bipolar, but i thought it was like minimized now. And he says "nice ***" all the time.. then 5 mins later he's picking out my flaws. What the hell is wrong with this kid?