LITTLE KNOWN FACTS ABOUT YU YU HAKSUHO!

Kurama's original manga color scheme was black hair and a blue uniform; the animators chose a red and pink version instead.

Kurama met Hiei when he was 14 years old.

It was noted by Yoshihiro Togashi in an insert segment of Weekly Shōnen Jump that in the first drafts of the series, Hiei and Kurama were to be in a relationship. However, due to the set-backs such content caused his previous works, he ultimately decided against making them a couple in favor of having them be close friends.

Kurama's Japanese voice actor, Megumi Ogata, also voiced Sailor Uranus from Sailor Moon. Ironically, Yu Yu Hakusho's author, Yoshihiro Togashi, is married to Naoko Takeuchi, the author for Sailor Moon.

Kuwabara means "mulberry field". According to Chinese legend, mulberry trees cannot be struck by lightning. Saying "Kuwabara" twice is supposed to ward off lightning bolts. It is also sometimes spoken as a means of warding off ghosts in Japan.

In both the Japanese and English dub versions of the anime, Kuwabara's Spirit Sword, when activated, has a similar sound effect to the light saber weapon of the Star Wars franchise.

Togashi came up Kazuma's name by combining the names of two professional baseball players. Coincidentally, a few baseball references were used in the series as well for Kuwabara. The manga version of the Genkai Tournament had Kuwabara wear street clothes, with a baseball jersey, as opposed to the anime where he wore his school uniform. Also Kuwabara had used his sword as a baseball bat on two occasions.

In the original Japanese and English dub, Kuwabara prefers to address Yusuke as Urameshi. However, in the English dubs of both movies, he always addresses Yusuke by his given name.

In almost every battle he has participated in, Hiei has lost his shirt either by his own choice or it being destroyed by his opponents. The only times this didn't happen were during his battles with Makintaro, Kuro momtaro, Bui and Sensui. Makes you wonder where he's getting all his shirts from, considering he's a loner.

Hiei is the only character of the main 4 to never resort to using his life energy in a match.

Hiei was only meant to be a starter villain but he was so popular that he became a main character.

In the Japanese version, George the Ogre's name is spelled Jorge, as his initials on his paper thin disguise is J.S.

In the Japanese dub, Karasu had a tendency to use English words when speaking. When talking to Kurama for the first time he specifically says "treatment" and "cool".

In the original Japanese version, Toguro chooses to go to Hell as soon as he reaches Spirit World. But, in the FUNimation dub version of the series Toguro chooses Limbo. It is well known from a religious point of view that these two realms are completely different.

Before he took up the role of Bui, Mignogna (the voice actor) had already voiced Ura Urashima of Team Uraotogi, but with a different voice.

On an interesting note. Each of the mythological creatures the Four Saint Beasts are based on (Turtle, Tiger, Dragon, Phoenix) interestingly symbolize the personalities of each of the Saint Beasts opponents. Kurama being wise and intelligent like the turtle, Kuwabara being brave and determined like the tiger, Hiei calm but deadly like the Dragon and Yusuke being passionate and having a habit of coming back stronger every time he dies like the Phoenix. Even more interesting is that Yusuke's energy took the form of a Phoenix and Hiei's best attack being in the shape of a dragon.

Jin is a likely parody of the wind affinity djinns, or genies of Middle Eastern mythology.

Gama bears a strong resemblance to a witch doctor, his demon powers even resembling those of Voodoo magic or various other tribal witchcrafts.

Raizen's name translates to "Lightning Buddhism", a likely reference to how he can fast for centuries without eating impurities, having a whole army of monks and being as strong and as swift as lightning.

Elder Toguro from the last part of the Spirit Detective Arc, the whole Dark Tournament Arc and near the end of the Chapter Black Arc is the longest lasting antagonist in the series.

Togashi based many of his characters in his second hit manga, HunterXHunter, off of the characters from Yu Yu Hakusho.

Sensui and his successor Yusuke on an interesting view are complete opposites in every possible sense from their views to their actions. Among these differences include that while Sensui became a spirit detective as a means to destroy evil and viewed it as an honor, Yusuke viewed it more as a chore. Sensui is refined, polite and calm, whereas Yusuke is hot-headed, foul-mouthed and shows no respect for authority figures. Even their respective fighting styles are different where Sensui uses the elegant martial arts style of Resshūken which revolves around kicks, Yusuke uses a brash street fighting style centered around punches.

Sensui and his successor Yusuke on an interesting view are complete opposites in every possible sense from their views to their actions. Among these differences include that while Sensui became a spirit detective as a means to destroy evil and viewed it as an honor, Yusuke viewed it more as a chore. Sensui is refined, polite and calm, whereas Yusuke is hot-headed, foul-mouthed and shows no respect for authority figures. Even their respective fighting styles are different where Sensui uses the elegant martial arts style of Resshūken which revolves around kicks, Yusuke uses a brash street fighting style centered around punches.

The Doctor's given name, Minoru Kamiya, is the same as one of Shinobu Sensui's seven multiple personalities.

Despite popular belief, Koto is not a fox demon. The Funimation dub, in which Yusuke mistakenly refers to Koto as a "fox girl", has led to widespread misconceptions about Koto's species. In fact, she seems to be a cat demon—she frequently meows in the manga, and in the Funimation dubbed anime she refers to her ears as "little cat ears" and is called a "kitten" by Bakken.

Chu's name literally translates to Sake, as a reference of him being a drunken fighter.

In the anime, the part where Keiko's long hair was trimmed and redesigned following her experience in rescuing Yusuke Urameshi's body from his burning apartment early on in the story was left unexplained to when she had it done. In the manga however, Kuwabara's sister Shizuru was the one who redesigned Keiko's hair after the incident.