Fish Devil

The Fish Devil (魚の悪魔)is a devil who embodies the fear of fish.

Appearance
Fish Devil has the appearance of a giant fish, with twin tails at its back end. Its only other distinguishing feature is its set of 6 seemingly bio-mechanical legs.

Personality
Nothing is currently known about the Fish Devil's personality except it presumably possesses hatred for humans like all non-humanoid devils.

Plot
At some point, Fish Devil had eaten a chunk of the Gun Devil's flesh.

Eternity Devil arc
The Fish Devil was killed by Aki and Himeno, and the Gun Devil flesh fragment was recovered from its corpse.

Abilities
Contract Creation: As a devil, the Fish Devil can bestow contracts upon humans for a price.

Blood Consumption: As a devil, the Fish Devil should be able to restore its health by consuming blood.

Revival: As a devil, the Fish devil should revive in Hell after being killed effectively making it immortal.

Trivia

 * Its appearance is very similar to Junji Ito's Gyo.