Mui

is the main antagonist that appears Naruto 5: Blood Prison. He is the of the prison castle Hōzukijō, and he is using the ultimate imprisonment technique to drain the prisoners of their powers.

Appearance
Mui has long black hair that goes beyond his shoulders. He wears some sort of suit with a brown belt and a silver buckle. He also wears goldish brown boots.

Abilities
Mui has shown great skill with taijutsu, able to defeat multiple prisoners bare handed without losing his composure, as well as easily defeat a weakened Naruto with a series of swift punches. He has also shown proficiency with fire release, which he can use to suround his arm with fire to use as a blade which can use to engulf those he stabs in fire. Most of all he has a technique which can bind a prisoner and prevent them from moulding chakra while at the same time absorbs their chakra after he applies a formula to them, it will also set them aflame should they try to escape. He also has an advanced form of this which he can use on larger targets.

Trivia

 * His name means "inactivity".