Hiei is a fictional character from the anime and manga series Yu Yu Hakusho, created by Yoshihiro Togashi. He is a powerful demon known for his speed and mastery of fire-based techniques, particularly the Dragon of the Darkness Flame. Hiei is often portrayed as a lone wolf, initially appearing cold and aloof, but he develops deeper relationships with other characters over time. Hiei is a member of the Makai demon realm and possesses a unique ability called the Jagan Eye, which grants him enhanced perception and the power to control others. Despite his tough exterior, Hiei shows loyalty to his friends, especially Kurama, and plays a crucial role in the series' battles against various antagonists.