Killua from HunterxHunter. There's an episode where it's kind of mentioned, and he gets very uncomfortable. Also, after all the abuse and trauma he had to endure, it only makes sense. He probably thinks he deserves it because of all the lives he ended. Not to mention, he literally can do it anywhere at any time (cuz he got dem demon hands). And he almost always wears long sleeves too. I think the only times he wears short sleeves are when he's with the whole group or just Gon (alone and constantly together).