Yusuke, a child delinquent (14 years old) saves a child from being hit by a car. However, in exchange, his life is taken. Do to some peculiar circumstances, he has the choice to be resurrected. He doesn't jump at the chance in the beginning, but soon is convinced to take the test to be resurrected. After a long process, (ep 5) he is resurrected. Thinking his life is normal, he goes around doing 'normal' things. However, he finds that he can see small demons. That is when he finds out he is to be a 'Spirit Detective' to help the After World (Rei-kai).
Botan is a nice, sweet, and quite bubbly girl who rides on a broom. However, she is 'Death'. (Liteally) She guides spirits to the Under World to be judged. Not a happy job (ep 54?) but she has to do it. She has blue hair and usually seen smiling (ep 1). She is also the one who guided Yusuke to the After World and who informed Yusuke that he was to be a Spirit Detective.
Keiko is Yusuke's school mate. She's very nice (unless provoked, which Yuuske does often). She is also the one who helped resurrect Yusuke (ep 5). In a way, she is Yusuke's girlfriend and one of his best friends. She often berates him for skipping school, smoking, drinking, and doing delinquent-type things. She has long brown hair.
Enma Jr. is Enma's son. He takes care of problems in the After World. He is the one who gave Yusuke the job as a Spirit Detective. Also, Enma Jr. is also the one who gave Yusuke the test to be resurrected. He is only about 2 or 3 feet tall. He looks like a child sucking on a pacifier but is acually hundreds of years old. However, when he comes onto earth, he changes (ep 40?) to an older body. He has light blue hair.
Kurama is a fox thief. After being hurt by a hunter, his soul enters The Human World as a child with red hair and green eyes. As a human, he can still use his botanical abilities. At first, he can only change to his real 'youkai' form once in a while. However, after the tournament (ep 50?) he is able to revert to his true form. As a fox, he is tall and has long silver hair with a tail. He using Makai plants usually when he is in his real form. He first meets Yusuke in Episode 6. He starts out as one of the three thieves who steal three treasures out of Rei-kai (After World/Spirit World). It turns out that he stole the Mirror of Utter Darkness to save his mother's life, the only person he had ever loved.
Hiei is a fire demon.
His mother and race of Ice Demons threw him off their ice continent because
his mother had twins, one being a Ice Demon and the other a Fire Demon.
The koorime (ice demons) kill all fire demon children not only because
they were different, but because the fire demons were their enemies. Hiei's
sister is Yukina, who he finds in the episodes around 20? She is also looking
for her brother. However, Hiei is either ashamed of his muderous past,
or afraid that she would be put in danger if she knew. Hiei's master is
Mokuro, one of the three rulers of Makai.
Mokuro. I don't know
that much about her except that Hiei has an interest in her, and she is
one of the three rulers of Makai. She doesn't appear very often, and I
think she only appears towards the end part of the series. She has brown/blondish
hair. I'm not very sure because I've only seen her on a card set and some
manga pictures. She is usually seen with bandages and covers all over her
body. Her body is scarred/charred by her former master. She took Hiei in
when he was young and alone.
Toguro was Genkai's
partner when they were in the tournament very many years back. He is also
angry at Genkai because she turned out to be old and not as powerful as
she became older. However, Toguro stayed young and only got stronger. Toguro
also kills Genkai later in the series, making Yusuke seek vengence. Toguro
has a brother. I don't remember his name but he has gray hair and likes
to change his body parts into swords/models, and weapons. Toguro is very
tall, muscular and has black hair.
Kuwabara has orange
hair. He is one of Yusuke's classmates. He starts out as Yusuke's enemy
and opponent. However, as the episodes increase, he becomes one of Yusuke's
closest friends and eventually joins Yusuke in his Spririt Detective business.
Kuwabara is best known for his skills to 'feel' a ghost's presense. He
also has very good reiki and joins in the tournaments Yusuke attends. Kuwabara
has a crush on Yukina, Hiei's sister.
A sweet, pretty, and
kind girl trapped for her tear gems. That is how she was first found. An
evil man help her prisoner because when she cried, gems would fall from
her face. So in order to make her cry, he would kill small birds in front
of her and do mean things. Hiei also cries tear gems, but Hiei never cries,
so you never see them. Yukina has long aqua-colored hair and wears a kimono.
She refers to Hiei as 'Hiei-san' and often asks him if he has ever found
her brother. I think that when she first saw or talked to him, she had
thought her was her brother but Hiei denied it.
An ex-spirit detective
who comes back to the Ningenkai to try to take it over.
Kurama/Minomino Shuiichi's
mother. In the third encounter with Kurama, Yusuke finds out that this
is the woman that Kurama will sacrifice his life for. She has heart problems
and was cured by the Mirror of Utter Darkness. However, Shiori does not
know that her son is actually a demon of another realm.