What can i do about my crush?

my crush is a big lets just say trouble maker.... he doesnt do his schoolwork he slacks off. he gets into fights and all my friends hate him excpt for my bfffffff. My old friend used to date her but he refuses to admit that because hes "too cool" for her but he told me that he likes me and that if i was a celebrity i would be his number one fan. i actually trust him and hes my best guy friend. but i told him no because the school year is ending and i will be going to Italy all summer and my ffriend used to date him. but i actually do like hi and i cant tell my friendsss. theyd freak. hes also very "innapropriate" when me and my bff r reading magazines he likes to look at the girls in the bras and underwear and he said "the grade11s r soo lucky they get girls with bigger "chest bumps' But idk what to do!!! OR HW TO TELL MY FRIENDS OR ANYTHING!! this is totally pissing me ooff