This yōkai was a member of the Orochi tribe. They were all killed by Mōryōmaru, but this yōkai was able to bit off a piece of Mōryōmaru's flesh with his poison fangs. He was killed when the piece of flesh in him overtook his body and absorbed him.
The wolf yōkai Kōga was continuing his pursuit of Naraku. He came across the yōkai who had collapsed. He explained to Kōga that a yōkai he had never seen before suddenly showed up and devoured all the members of his tribe. He survived after he bit off a part of his flesh and injected him with poison through his fangs. Suddenly the flesh that he had bitten off expanded within his body and absorbed him. Kōga recognized the flesh's scent as Mōryōmaru's and pursued the flesh. It returned to Mōryōmaru's arm that was waiting on a pile of dead Orochi tribe members. It attacked Kōga in order to steal his shards of the Shikon no Tama. Kōga soon realized that the reason Mōryōmaru attacked the Orochi tribe was to gain their poisonous abilities after he saw the arm melt rock with Orochi tribe poison.