sex addict?

I am sexually active on Saturday nights with a man I believe is a sex addict. He has a 2yr relationship with a girl he’s been living with. (I didn’t know when I first was hanging out with him) I meet him out every weekend and we drink, dance and have a great time including sex. He is always trying to meet and hook up with other girls asks me if I would do a three some or if I have friends for added fun. He always dances on girls to rub against them, he flirts, persues everyone and gets phone numbers glore. He buys girls roses and gives them attention, he goes a lot of times for the girls that probley would not get guys. But at the end of the night he always ends up with me, and I with him even though I should not be involved for any reason with this man. But there is something about him that attracts me. I also feel like he is very needy, always tells me how much he likes me (ofcourse to get what he wants) he always asks questions about how much do I like him and if he pleases me and always wants to cuddle me real close and tight. I have heard form other girls that have been with him and there has been a lot that he just keeps moving on. We met at a Halloween Party and he had sex with 3 different girls at the party that night (1 of them being me) I know I should run really quick but I really like him and I feel like the way he acts so uncontrollably that there is a real problem. Is there any way for me to talk to him about this?