Kuronue
Kuronue was first seen in the Yu Yu Hakusho movie: Poltergeist Report. Kurama recodnised him from the past as his partner while thieving. During the theft of a mirror, a bamboo spear pierced through the bat demon’s favorite necklace which appears to be made of ruby and gold. Despite Youko’s cry of protest Kuronue went back after it and was pierced through the major arteries with bamboo spears, utterly ending his life. While Kurama is now a member of the party of Yusuke. A demon disguised as Kuronue attacks Kurama while he is alone.
All information found in the movie, Yu Yu Hakusho: Poltergeist Report.