Onsute resembled a insect with a long extended neck and shelled armour. He had a large horn and deep sunken eyes, at the sides of his mouth were pairs of mandibles.
After Akira Fudo had gone a killing spree on the demons that had attacked Tokyo, he is knocked out byPsycho Jenny. Immediately afterwards Fudo is surrounded by demons among them being Onsute, who tries to kill him while he was down, alongside the over angered demons. Fudo however is saved when Zann comes down and tells them that Akira is to be left alive due to the wish of Satan.