Kurei is Recca's older half-brother, born in 1571, four years before Recca. He is the firstborn son of Flame Master Ōka and his mistress Reina. Initially recognized as the next leader of the Hokage clan due to his innate flame powers, Kurei was labeled a cursed child when his younger half-brother, Recca Hanabishi, also exhibited similar abilities. Instead of being killed to save the clan, Kurei and his mother were exiled thanks to Kagerō's intervention. Kurei attempted to kill Recca but was imprisoned for his crime. He escaped during Oda Nobunaga's raid on the Hokage village by jumping into a time portal opened by Kagerō to save Recca.
Afterwards, Kurei was found and adopted by Tsukino Mori, the wife of Kōran Mori, one of the series' main antagonists. Kōran raised Kurei to become emotionless, telling him that human emotions were unnecessary. Upon noticing Kurei's love for his mother, Kōran had her transferred and placed under house arrest. When Kurei fell in love with Kurenai, Kōran's adopted daughter, Kōran had her killed, causing Kurei to despise his adoptive father. However, Kurei obeyed Kōran because he held his mother hostage.
Kurei leads the Uruha, a group of skilled warriors serving Kōran Mori and assisting Kurei in missions assigned by Kōran. Like his father and half-brother, Kurei can produce and manipulate fire. His primary flame form is the Phoenix, which appears purple in the anime and a different shade of red in the Flame of Recca video games. Kurei has the unique ability to absorb souls into his flames, creating humanoid flames that obey his commands. The first soul he absorbed was Kurenai's after she was killed by Kōran. Later, he absorbed the soul of a loyal Uruha member named Jisho, though this event is not depicted in the anime or video games.
Besides his flame-based abilities, Kurei can perform non-flame techniques such as Wakemi, which allows him to create multiple solid duplicates of himself with his powers and skills. In the final part of the manga, he uses Jikuryūri, a technique that enables him to open a time portal.
