Confused with a dude

Soooo ive been fucking this guy since like December. I guess we are fWB. There’s no feelings there. At least not on my part. I’m still dating other guys. I don’t ask about his life and he doesn’t ask about mine. I was recently told he’s had a girlfriend for a while. Every time he gets drunk he calls me and always wants me to come over. I only go over when I’m in the mood. Then he gets upset and tells me that he knows I have a boyfriend which I do not. I don’t know what to do about the girlfriend thing. Helpppp