Guys point of view on relationship?

I've been seeing this guy (we were friends before we started having sex) for seven months now, though we're not officially boyfriend and girlfriend. I know that because we're not official technically either of us could have sex with/see someone else, but when we're together he always says that he doesn't want me with anyone else, and he's suggested that he isn't (although whether he actually is or not I don't know.. not really my business). Recently when we've been having sex (which he knows he'll get anyway so this is not just a ploy to get into my pants or anything) he sometimes refers to it as "making love" (like saying 'do you want to make love' rather than not saying anything or referring to it as 'being frisky' or something casual like that which he would previously have done. He's always extremely affectionate, even when we're out with his or my friends (and we also have quite a few mutual friends), holding hands, stroking me, kissing me (all of which he initiates). We hang out a lot and message/call each other a lot, although sometimes I won't hear from him for a few days which really confuses me. The fact that we're still not actually official does as well. I'm just not sure what this relationship is! Any ideas?