Ryūrimaru

was Hisen's summoning creature that appeared in the light novel adaptation of Mission: Protect the Waterfall Village!.

Background
Ryūrimaru was summoned by Shibuki in his battle against Suien.

Personality
Ryūrimaru was obedient and loyal towards its summoner, Hisen.

Appearance
Ryūrimaru was a crimson white catfish that was six times the size of a human man.

Abilities
Ryūrimaru had the ability to use the Transformation Technique. With Hisen saying, "Dragon God Transform", it transforms into a giant golden dragon.