The way the meme works is that the humor comes from the fact that the "superior" option is actually the one that's strange or embarrassing, which implies that the author is both deviant and lacks self-awareness. It's deliberately self-deprecating.
Its incredibly common to be thrown by this. Like many memes, the original incarnations were to be taken at face value, but then a layer of irony got applied, and the ironic/self-deprecating variant became the norm.
I mean, this meme is used all over lemmy, and it's usually the same thing, someone comparing why they do something to someone else and the context is usually to feel superior.
What I'm saying is that the meme is usually used ironically. Here the OP is saying that he has a sexual fetish for a type of woman who doesn't even exist. That is not something normal people respect or admit to. So the joke is that he thinks he's superior but actually he's not.
Then there's a level of meta-humor because the OP is probably actually attracted to monster girls. So he's a weirdo pretending to be a normal person pretending to be a weirdo. But he's posting to a community of weirdos, and in that context he's actually a normal person...