Basically anything that is more likely to be seen in a snuff film than everyday life. Anyone who's turned on by mutilation, cannibalism, bodily functions, etc. is pretty messed up and should probably find a hobby.
Also, furries (not counting the ones who merely identify with animals nonsexually because I'm sure one will take not and tell me I'm generalizing. It's okay, you guys are weird for different reasons). Being attracted to animals is one thing (still weird), being attracted to animals with human features is all kinds of creepy. It's the uncanny valley thing that really gets me. I find most furry art disturbing even if it's not overtly sexual. Human torso, dog head, anime eyes...ugh.
Also, furries (not counting the ones who merely identify with animals nonsexually because I'm sure one will take not and tell me I'm generalizing. It's okay, you guys are weird for different reasons). Being attracted to animals is one thing (still weird), being attracted to animals with human features is all kinds of creepy. It's the uncanny valley thing that really gets me. I find most furry art disturbing even if it's not overtly sexual. Human torso, dog head, anime eyes...ugh.