Jailer Beasts

The Four Demon Guards are the most fierce guardians of the Undersea Gaol, Impel Down, aside from the Warden Magellan. They appear to be under the command of Sadi-chan. This group consists of Minotaurus, Minorhinoceros, Minokoala, and Minozebra.

Appearance
The Four Demon Guards are gigantic bipedal animals that wear pants but no shirt, with the exception of Minorhinoceros, who wears overalls. In chapter 544, Crocodile reveals them to be "awakened" zoan users, which must mean they either chose to voluntarily assume their hybrid forms, of stuck that way due to their "awakened" status. They each have runny noses and cutesy eyes (except Minozebra, who has a bored look). They all have comical and harmless appearances, despite their feared reputations. Like many of the important crews and groups in the series, Demon Guards all have animal themes:
 * Minotaurus: A giant bipedal cow with a spiked mace.
 * Minorhinoceros: A giant bipedal rhinoceros in overalls with two spiked maces.
 * Minokoala: A giant bipedal koala with spiked knuckles around its wrists.
 * Minozebra: A giant bipedal zebra with a spiked mace with a long shaft.

Personality
Despite their comical and harmless appearances, all four of them are ruthless creatures who brutalizes the prisoners of Impel Down, making them the most feared creatures within its walls, second only to Magellan. Minorhinoceros is also bashful, while Minozebra is shy. However, they do seem to fear Sadi-chan when she gets angry with them.

Abilities
The Four Demon Guards are the most feared creatures within the confines of Impel Down due to their great strength coupled with their blood lust and ruthlessness. They are "awakened" Zoan users, wich mean they are much stronger and can recover much faster than most of the others Zoan.
 * Minotaurus: He has incredible speed and strength, which, combined with a giant mace he carries, makes him a lethal force to be dealt with. He is also very resilient, taking heavy damage while ignoring the pain, and standing back up to fight, until before being completely knocked out.
 * Minorhinoceros: Wielding two spiked maces, its full abilities are not yet known.
 * Minokoala: An armed fighter wearing spiked knuckles, its full abilities are not yet known.
 * Minozebra: Using a mace with a long shaft, it threw a number of prisoners into the Pond of Blood, its full abilities are not yet known.