 Shrieker is a frog-like hollow with bat elements and the ability to summon numerous explosive minions.Shrieker was a serial killer in life who died when a boy Yūichi Shibata attempted to save his mother from the murderer.After becoming a Hollow, Shrieker gets revenge on Yūichi by placing his soul in a parakeet and lying that he can revive the boy's mother if he evades him for three months.