Confused and think "straight" friend is not really straight.

I am writing because I am questioning someone else’s sexuality. Full disclaimer, I usually operate on the basis that whatever people say, I believe, no questions asked. However, this situation has got a bit personal and I’m tangled a bit in it.

Our workplace went together for Pride a few months ago. There was someone who works in a different office (yes it’s someone from work, but it’s not someone from my office) but we got a big work group going. He thought I was straight as when I was talking about an ex he defaulted to the “she” pronoun, but I clarified it was another guy. He then told me he was straight. Not much else.

Then, he proceeded to get very drunk. We danced. I thought that was normal. He started commenting on the hot guys he saw. I thought he was being an overeager ally. We danced some more. Then we made out. A lot. For a few hours.

It’s not just the make out session we had. He got very grabby. I’ll spare the details but his hands were basically all over me. He told people around as we walked around booths buying beer and so that I was his boyfriend. I asked him why, he said “it was easier”. He even said that he wished he was gay so that he could date me. (There were a lot of random drunk comments.) Then he said that maybe we should come back to mine. I asked him if he was sure. He sort of excused himself and went home.

I thought this was weird, to say the least. We met up a few days later and clarified it over a coffee. He just asked me if we were “cool” (I said we were) as he was worried we weren’t. He apologised for being too forward. He acted like it was the most normal thing. And I know I’m not the first guy he made out with. I’m the first one that is not some random guy though. He has never slept with a guy, and claims that’s where he draws the line. That’s why he considers himself straight.

I then thought that maybe, just maybe, his sexuality is indeed something like “straight but likes making out with guys when he’s drunk” and that the world is just more complex than I can ever understand.

But. Some of the times we’ve been out drinking together again, he’s started hitting on me. This has already happened a few more times than I can count. Over the last few months. Sometimes he clearly hits on me, some other times he just makes a weird comment (for example, last night he said I should take my t-shirt off).

The other thing is, a few weeks ago, we were at a house party and I brought a friend of mine. For some reason, after he drank, he started blabbing to my friend. Context, he’s seen him a few times but while he’s my friend, they’re more like acquaintances. He just told him that he didn’t know what to do because he found men attractive. And he still liked women. And he even pulled out the “why do I have to be straight or gay or bisexual” (aka the “screw labels” argument) and my friend listened to him and later on told me about this. And he added “your friend is very confused”.

So I think I have some pretty good arguments for thinking he’s maybe bisexual? I don’t know how to proceed. I may be a bit interested in him as well. But I think this is too complicated to have a good result in the end. Still, feel free to chime in.