How would you feel about all of this?

He's using you DUH! From a guys point of view he made a deal for free with no strings and with stupid girlfriend/boyfriend drama attached. Why would he want to mess up a good thing? No man would in his situation to be attached to 1 woman who believes they are anymore special than the other girls he easily beds. If anything leave and if he makes an effort to go after you without involved, which is highly unlikely, then you know he likes you for you not for .