OVA
Description
Hiei was born in the Country of Glaciers to the ice maiden Hina and an unidentified fire demon. His existence violated koorime laws against interracial breeding, branding him an "imiko" (cursed child) believed to bring disaster. Shortly after birth, his mother's friend Rui cast him out while restrained tribeswomen ignored Hina's pleas. Banished with him was an icy tear stone (hiruiseki) shed by Hina during the expulsion.

Demon world bandits found and raised him, bestowing the name "Hiei." He inherited his father's violent nature, developing a brutal personality, yet found paradoxical calm through the mysterious power of his mother's tear stone. This object stirred nostalgia for his homeland, driving a search that ended when he lost the stone in battle. To relocate it, he sought the Jagan Eye. The demon Shigure performed the forbidden surgery to implant this third eye, costing Hiei his original A-class demon powers and forcing him to relearn combat through swordsmanship under Shigure.

Possessing the Jagan Eye allowed Hiei to discover his birthplace, but he lost interest and returned to thievery. He stole three Spirit World treasures and fled to the Human World, leading to his first encounter with Yusuke Urameshi. Though initially defeated and arrested, he formed a contractual alliance with Spirit World to assist Yusuke in investigations, reducing his sentence. During this period, he located his twin sister Yukina, trapped in a barrier, but chose not to reveal their kinship after her rescue.

Hiei fought with Team Urameshi in the Dark Tournament. Beginning with D-class demon power, he advanced to B-class by the finals. He remained undefeated, mastering the Dragon of the Darkness Flame and developing a dragon tattoo on his right arm upon gaining control of the technique. His stated wish for victory was "the lives of all the tournament's organizers."

After the tournament, Hiei sought the Chapter Black tape to justify his hatred of humanity but destroyed it upon obtaining it, reflecting a shifted perspective. During the Demon World saga, he joined forces with Mukuro, a demon king whose traumatic abandonment mirrored his own. He rose to become her top aide, freed her from psychological shackles, and delivered her abusive father as a "birthday present" in the manga continuity. He competed in Yusuke's Demon World Tournament but was defeated.

In the Eizou Hakusho: Opening & Ending Encyclopedia OVA, set after the main series, Hiei attempted to return Yukina's tear stone at Genkai's residence, claiming her brother was likely dead. Yukina responded by asking him to keep it, implying recognition of their kinship. Genkai noted Yukina had matured beyond needing protection. Hiei later appeared at a beach reunion with the core group, engaging in characteristic bickering with Kuwabara. Kuwabara teased him about his relationship with Mukuro, which Hiei neither confirmed nor denied.

The OVA also revealed Hiei spent the next four years patrolling Mukuro's territory, returning humans who strayed into Demon World. He wore Mukuro's tear stone necklace, symbolizing their bond and his intent to return. His primary costume—a black cloak-like jacket, white headband concealing his Jagan Eye, and arm bindings later replaced by a dragon tattoo—remained consistent throughout his appearances, making him the only core character without significant outfit changes.