RayRay

I think your co-worker is "too much". There are something you can do but depends what is your direction.

If you staying in this company, you may need another co-work to talk to this dude and finding out what is wrong with you and what is wrong with him. Then you can figure out what to do !

If you want to quit, tell your boss you want to quit and you want to invite this dude have a meeting with you while your boss around. Your need your boss to "protect" you if this dude doing something in-appropriate. After the meeting, you are well protected by yourself and leave all subsquent event to your boss.