WHAT DO YOU THINK???????

My friend is gay/biual because he has boyfriends but he constantly flirts with me and even told me that he liked me before...the other day he kissed me. I tried not to fall for him because I know he talks to guys but its really hard. when I see him with other dudes i find myself getting kind of mad but i never really show it and when i talk to other guys he always has some snappy comment of why shouldn't be with them. I don't know what to do because i'm trying to figure out what should i do about the way i feel and how he feels about me . its like were on the boder line between friends and something else please help. no rude comments please.