A chief executive of Zenom Organization. Baku appears to be Sect Crescent's most trusted agent, and seems to know a great deal about the nature of the Kaballah.
Effect:Telepathy and teleportation when used with the two other masks possessed by his son and daughter respectively.
Post-timeskip, in combat he was also shown to be skilled with knife-throwing and creating illusionary duplicates of himself, although it is unknown if the illusions are the effect of an O-Part or not.
During Jio's battle with Sect Crescent, Baku was possessed by Miko in order to steal the other half of the Legendary O-Part, his face even transforming into Miko's. After Miko provoked him enough, Jio punched Baku's body and sent it crashing into a wall. It is currently unknown if Baku is still alive.