For decades, it's been a staple in many comedy anime for a character to get a nosebleed when they see an attractive person. It's almost as old as the genre itself. Those who grew up watching anime in the '90s and early '00s have probably seen it happen at least once, especially when watching shows with a lot of fan service. But why do anime characters get nose bleeds when they encounter someone they find attractive or catch a peek at a scantily clad member of the opposite sex?

The root of the anime nosebleed trope lies in superstition reflected in art. The concept of the nose starting to bleed because of sexual arousal is one of these superstitions. Like many superstitions, there is often a grain of truth somewhere at the root, but how true is that in this scenario? The real question on everyone's mind is whether it's scientifically possible in real life for someone to get a nosebleed because they are excited or aroused.

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Where Did Anime Nosebleeds Come From?

Jiraiya drooling over naruto's sexy jutsu form

Anime and manga have a lot of interesting tropes, including the nosebleed trope. Characters can often be seen with a snot bubble that indicates them sleeping, while others seem to have a perpetual drop of snot leaking from their noses that indicates their emotional state. None is as strange as the nosebleed trope, however.

Based around an old superstition, the anime nosebleed trope suggests that when a teenager filled to the brim with hormones sees something arousing, their blood pressure rises to the point that it causes a nosebleed. Mangaka Yasuji Tanioka's humorous comics from the '60s are thought to be the trope's earliest inclusion in manga. Usually, its usage is accompanied by a panty shot or when a character looks more attractive than normal.

In the Naruto anime and manga, for example, Naruto and Konahamuru practice their "sexy jutsu," which allows them to turn into a beautiful woman, usually wearing barely any clothes. The result often finds the surrounding men, like Master Ebisu, Kakashi or Jiraiya, spraying volumes of blood from their noses as their eyes bulge out of their faces.

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Anime Nosebleeds and the Lecherous

Chopper Watching Sanji Fall with a Nosebleed Cropped

Yuru Yuri's Chitose is notorious for getting them whenever she fantasizes about her friends getting together, mainly Kyouko and Ayano. Master Roshi is also associated with nosebleeds, being the old lecherous man that he is. Ever since Dragon Ball was first released, he has been used as a prime example of the nosebleed trope. His first bloody nose was caused by Bulma flashing him. Since then, he's usually the character that comes to mind when someone thinks about anime and nosebleeds. One Piece's Sanji is another example of a lecherous man getting them frequently.

Another example of the anime nosebleed, albeit an extreme case, is Karin Maaka from Chibi Vampire. While not necessarily stemming from arousal, she has some of the heaviest nosebleeds in anime history. Her waterfalls stem from the fact that she is a "reverse vampire," a vampire that produces an excess amount of blood rather than craving it. She targets unhappy people, and when she bites them, she gives them an injection of her blood, which brightens their moods.

While they are usually depicted as a normal red color, sometimes instead white steam is shown. Usually, these are shown in shows for smaller kids. It is used to express general excitement rather than arousal. Pokemon's Brock is a good example of this alternate version. Many times, the blood is censored for international audiences, and steam is used instead.

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Anime Nosebleeds Are Not Scientifically Accurate

Pokemon's Brock Hormonal Nasal Steam

So, how possible is it to get a nosebleed from sexual arousal? To answer this, let's look at the two most common causes of nosebleeds. The first is nose picking, and the second is being exposed to dry air for extended periods of time. The second reason is why they are more common during the winter months. High blood pressure is another cause of nosebleeds, but it is not a general symptom. Nosebleeds only tend to occur from high blood pressure during a hypertensive crisis, when the rate rises to 180/120 or higher. Even then, it is not a common reaction, happening in only about 17% of cases.

There is also anecdotal evidence of people who have gotten them from having overly zealous sex, which could be a result of extremely high blood pressure due to overexertion. On a scientific level, however, there is no evidence for sex-caused nosebleeds. Dr. Kouichirou Kanaya, who is an ear, nose and throat specialist, says in a NicoNico News interview that while high blood pressure and an increase in heart rate are definitely caused by sex, nosebleeds are something that have no connection to it. In short, an average person cannot get a nosebleed from having sex. There is evidence, though, that men who take performance-enhancing drugs such as Viagra can have nosebleeds as a result of the increased blood flow.

While it's already been pointed out that it's not just lecherous men, young and old, who fall prey to this reaction, there are a variety of medications on the market today that could cause random nosebleeds, making everyone a potential victim of this embarrassing trope. In essence, this only serves to support the trope's continuation.

Overall, the nosebleed trope in manga and anime is a perfect way to express the pent-up hormones of teenagers and lecherous men (and sometimes women), even if it has no basis in science. Unless someone is taking specific medication that induces a bloody nose as a side effect, the likelihood of getting one from excitement or arousal is slim to none. That doesn't mean it isn't funny when it happens to a character because they got too excited after seeing a pair of panties, though, or when a vampire produces a waterfall of blood instead of consuming it.