The Mouth Monsters are a group of 3 NPCs that appear in the Mural World and Underground World.
They are small creatures consisting of a mound of hair and a large mouth with red lips and wide, square teeth. Each has a unique hairstyle and gives this to Madotsuki as an effect.
Curiously, each Mouth Monster is found wandering around near a blood splatter, one for each individual. What this represents, as with everything else in the game, is a mystery. Furthermore, no Mouth Monsters are ever seen where there are other types of NPCs in the vicinity. The implication may be that they have eaten another creature and wear their hair as a trophy, which perhaps explains why Madotsuki can take it off them.
Interaction
All three give effects that change Madotsuki's hairstyle when interacted with:
- The one with brown hair gives the Long Hair effect
- The one with blonde hair gives the Blonde Hair effect
- The one with the hairstyle that looks like a fake dog poop gives Madotsuki the poop hair effect.
They otherwise ignore Madotsuki, but show the standard reactions to the Knife, Cat and Stoplight effects.