If you don’t like him being with other girls, tell him that you aren’t comfortable and he has to either choose to stay with you or leave. Of course ONLY IF YOU DON’T LIKE HIM BEING WITH OTHER PEOPLE, tell him now and don’t keep around an unloyal man. It’s going to suck if he leaves you I know, but it’s better to get rid of a cheater early than to get even more attached than you are. Don’t do anything if you aren’t certain it’s what you want, but I personally would tell him right now that he has to choose