The evil Utukkus from Akkadian lore. The ghosts of those not buried the right way. They were vengeful towards the living and would possess those who broke taboos. They caused disease and criminal behavior and were considered wind spirits that sucked the life out of the young.
Edimmu appears as a miniboss in Nakano's Stone Site silver level instance, Ueno's Mirage instance, and part of the Lord of the Flies series of quests. The ability to fuse him is acquired through completing tasks for the master of the cathedral in Shinjuku Babel. He's a special fusion of Raijuu and Jinn.