I agree with littlewing too. He got drunk , he got horny, he got laid. Now he is backing away from it because he doesn't want any more complications that might come from admitting something happened that he remembered or that he was in control of. Bart Simpson does the same thing all the time "I didn't do it!". He used you (you may have used him too). He's irresponsible and you'd be better off chalking it up to experience and learning that casual sex may not be all it's cracked up to be. I hope you used condom(s) ...it sounds like you both subscribe to the concept of sex as recreation.
-------
A Parent, old geezer, and occasionally right. Good judgment comes from bad
experience, and a lot of that comes from bad judgment.