Most people don't know why a male character will get a bloody nose from seeing a woman (usually without clothes). The reason behind it is an old Japanese tale saying that states: "If a man ever looks at a woman with impure intentions he will be cursed with a bloody nose." Or something to that extent. Notice girls only get a blush around the cheeks and never a bloody nose. (ex. Seen in Devil Hunter Yohko)

2) Sneezing

Sometimes people will suddenly sneeze after hearing their names mentioned. There's another myth that says if someone is gossiping about you or cursing your name you'll sneeze. (ex. Seen a lot in Ranma 1/2)

3) Sleeping

In comical moments when people are sleeping they have a bubble in their nose. The best way to wake these people up is to pop the bubble. Reason still unknown to me why it works this way. (ex. Seen in Utena and even Zelda: Legend of Oracles)

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