Well I think it would’ve been offensive since it’s being posted to r/joke, and the punchline being that the person revealed they were trans and the person left isn’t much of a joke.

But you’re right in that in real life, people have their own preferences when it comes to attraction, and that’s ok. 🙂 I would, however, say that if OP’s character was already attracted to Christian/Christine, and only became un-attracted once they found out they were trans, I think OP could ask themselves why that is if they wanted to get to know themselves better.

The joke is that the character thought the trans character was talking about being religious, whereas they were trying to tell them they were trans. The joke is the confusion due to the word Christian being used as both a personal name and the name of a religion.

But it’s just poking fun at the wordplay around the word Christian isn’t it? It might be related to being trans, but it’s not offensive because it’s not being negative towards trans folk.

If the joke had ended with OP’s character leaving as a result of the reveal, then I could see the offence. But OP’s character could just as well be like ‘haha that was a good one! So how are you?’.