What is the silliest/strangest thing about someone's body that instantly put them in a "nope" category for sex/dating?

First, I'd just like to say I'm not here to yuck anyone's yum. I also understand that no one gets to choose how their body is made (excluding obvious plastic surgery procedures). We all have preferences. Hopefully, we can all keep this civil (welcome to the internet, I know), but I'm genuinely curious about some that other people may have because a few of mine have been so random.

I once really liked a guy who was smart, funny, fit, the whole package really, but his ears looked underdeveloped in some strange way that's hard to describe. It made me uncomfortable for some reason, and I just couldn't get past it. Such a stupid reason to disqualify someone, but my brain wouldn't let go of it. 🤷‍♀️