Hiei was born a fire demon to a clan of ice maidens (Koorime), an all-female race that reproduces asexually. As a male child born out of a forbidden union, Hiei was seen as an abomination and was cast out of the clan shortly after birth. Left to fend for himself, Hiei grew up in the harsh Demon World, developing a survivalist mentality and a profound distrust of others.

To strengthen himself and exact revenge on his persecutors, Hiei underwent a dangerous surgery to implant the Jagan Eye, which enhanced his abilities and allowed him to locate the ice maiden clan. His search led him to learn about his estranged twin sister, Yukina, whom he vowed to protect from the shadows without revealing their familial connection. Hiei’s life took a turn when he joined Yusuke Urameshi’s team, shifting his focus from vengeance to fighting for a greater cause.

Hiei is short in stature but physically imposing, with spiky black hair and a white starburst pattern on his forehead. His crimson red eyes exude a fierce intensity, and his lean, muscular build reflects his agility and combat expertise. After the implantation of the Jagan Eye, a third eye is visible on his forehead, symbolizing his mastery over dark abilities.

Hiei is often dressed in a black cloak or sleeveless martial arts outfit, which emphasizes his pragmatic and no-nonsense approach to combat. His distinct appearance underscores his role as a deadly and enigmatic warrior.

Hiei is cold, stoic, and often aloof, preferring to rely on his strength rather than forming close bonds. His harsh upbringing instilled in him a survivalist mentality, making him wary of trusting others. However, beneath his hardened exterior lies a deeply loyal and protective nature, especially toward those he considers friends or family.

While Hiei often exhibits a dry sense of humor and biting sarcasm, his actions demonstrate his willingness to risk his life for others. His internal conflict between his demonic instincts and his evolving sense of morality adds depth to his character, making him one of the series’ most compelling figures.

• Spirit Detective Saga
  Hiei is introduced as an antagonist working with Kurama and Gouki to steal mystical artifacts from the Spirit World. During this arc, he nearly kills Yusuke but is defeated and imprisoned. His motivations are later revealed to be more complex, and he becomes an ally of Yusuke after earning a second chance from Koenma.

• Dark Tournament
  Hiei’s skills and powers shine during the Dark Tournament, where he becomes a key member of Team Urameshi. His mastery over the Dragon of the Darkness Flame, a devastatingly powerful technique, establishes him as one of the strongest fighters in the series. His battles, particularly against Seiryu and Bui, highlight his relentless determination and tactical intelligence.

• Chapter Black Saga
  In the Chapter Black Saga, Hiei’s role expands as he confronts morally complex challenges alongside his team. His ability to navigate the gray areas of morality proves vital in their battle against Shinobu Sensui and his followers.

• Three Kings Saga
  Hiei’s past and origins come to the forefront in the Three Kings Saga, where he is summoned to serve Mukuro, one of the three rulers of the Demon World. Through his interactions with Mukuro, Hiei confronts his past traumas and solidifies his identity as both a demon and a member of Team Urameshi.

• Three Kings Saga
  In the final arc, Yusuke learns about his demon lineage as a descendant of the demon Raizen. This revelation forces Yusuke to reconcile his human and demon identities. He participates in a tournament to determine the ruler of the Demon World, ultimately finding peace in the balance between the two realms.