Not just with Alan. Serena just had sex with the guy that showed up after the party ended. They were laying together on the couch, he pulled his pants down just far enough to pull his dick out and he tried to poke her from behind. She did not seem to like that, so she got on top of him, they had sex for a while, then finished him off with a blowjob. He tried to kiss her a few times but I think she just wanted to get him off and be done, which is what happened.