Gay guy keeps haring me? (im straight)?

Theres this gay guy were i work at who keeps on hitting on me and im really getting pissed off, he asked me out last week and i told him no, and that i only like women. He said that he understood, but now it seems like he is only trying harder, i tried to avoid him the following day but he kept following me,trying to start a conversation, so we talked about random stuff and then he told me how he was really attracted to me and that i should give him a chance, i denied him again telling him that i was strait and that i love girls to much, anyway, one of the girls who i work with told me yesterday that he said he was going to "turn me out" before the summer ended. Little did he know, was the girl he told is my ex girlfriend and very good friend of mine, so i confronted him about it, and we got into a big argument, he called me a , and that i was a bigot, i ended it after that and told him not to say anything to me for the reaminder of the summer or we will have problems (physically), about a hour ago he called me telling me how he wants my body, now i dont know what to do, i dont want to file for ual harrasment, cause that will be embarrising, and when i said i was going to fight him, i was just bluffing, he's twice my size, but now i dont know what to do, my brother said that we and a couple of friends should jump him, but i dont like the idea of teaming up on a gay guy (it sounds bad on a police report), it has gotten so bad now to the point were i just want to leave my job, im 18 btw and he's like 21 i think, anyways idk what to do.