Undertakers

The Undertakers (墓守 (アンダテーカー) Andāteikā) also known as the Anti-Deadmen Corps are a special force created by Tsunenaga Tamaki. They're the worst criminals who survived the "special correctional program". The Undertakers possess technology called Worm Eater that allows them to nullify a Deadman's Branch of Sin.

Two years prior to the beginning of the series, Genkaku killed Nagi Kengamine's wife and this caused Nagi to go insane and massacre 22 Undertakers. Since then, Genkaku has continuously tried to get Nagi to join the Undertakers. The Undertakers had a large role in Scar Chain's mass prison break, as they were Scar Chain's direct enemies.

Trivia

 * The foot soldiers of the undertakers are shown to be not only murderous but completely immoral as shown when they attempted to gang rape Shiro and Karako when they were both captured by Azuma.