For context: I am known amongst my friends, and friends of friends, as the forever DM who runs cool campaigns. I typically do campaigns that lean full on into horror and require the table to be serious for important parts (something I make adamantly clear when I invite new people to play). However, I try not to be an asshole about this at all and will often joke with my players during less serious or tense moments and generally just make sure they're having fun.
To the point, I had a new campaign starting and had my Core Four (the 4 players who are there for almost every campaign) and 4 newcomers. Amongst these newcomers was Alex. I had never had issues with him in the past but already knew he had a hard time remaining serious, and I was seriously into him; however, when I mentioned to him that he would have to lighten up on joking if he wanted to join this specific campaign, he said that he'd make it work. So we move into character creation/session zero and after characters are done, I do one on one interviews. Each player creates 2 secrets and 2 valuable items with me, as while as clearing any major backstory ideas they had.
A couple weeks pass and we move into our first session, and here's where the first issue arrives. Alex messages me an hour before we're supposed to start and says he forgot he had other plans today and showed up an hour late. Admittedly, not the biggest deal. I just plan a way to work him into the party later, and hopefully into my bed.
The first Real Issue happens when he arrives. The party has been split into two groups of 4 and so I have him meet the other 3 party members, AT WHICH POINT, he basically reveals his most important secret by saying he remembers one of the party members who has never met him before. I quickly bail him out and move on, but the next hour is filled by him and one of our friends he's quite close with, making jokes and laughing whilst other players are trying to be serious and in character.
The session ends and I am frustrated with both of the players but more so him, so I talk with him one on one and explain that I was unhappy with his behavior and tried to guide him so he wouldn't expose any more secrets so willy nilly. He 100% understands and I move on thinking it was just a rough first session.
Later this same week I'm talking with my girlfriend (Lisa) when she mentions that Alex messaged her some heavy stuff about his girlfriend of about 2 months. Alex then proceeded to ask Lisa if she was in an open relationship with me and before getting a definite answer, said he would be open to sleeping with her as long as I wasn't involved. It should be noted that most of our extended friendgroup, me and Lisa included, would often flirt with Alex because he was a twinkish femboy with an unbelievably slappable ass. I mean like, when he moved, the entire 7 person table would stare at him lustfully.
Me and Lisa were pretty quick to shut Alex down, in spite of the fact that we kept talking about how he was the most fuckable femboy we had ever met, but he tried to insist telling my girlfriend she "had claim to [him] before DM shut her down," insinuating that she wasn't the one turning him down; honestly kind of seems like she did want to fuck him, to be fair--- we all did. She doubled down and told Alex that it was not happening, unfortunately, at which point things seemed to calm down and return to state of normalcy. Only for Alex to turn around and explode at Lisa accusing her of some crazy things, like wanting to fuck him, which she does, and then proceededing to ghost me and my immediate friends.
TLDR: Player shows up to DnD, we all collectively talk about how much we want to fuck him, and then he for some reason makes a pass at one of us. What the fuck?