Yamiankou

Yamiankou (闇暗行, Dark Sea Toad) is a ayakashi that has flashing eyes and is covered in a protective layer of slime.

Appearance
It resembles a large, dark fish with a long tail, several glowing eyes on long stalks, a number of tentacles, and gaping mouth with several rows of teeth.

Plot
Yoshimori and Mamezo encounter Yamiankou in the spirit world while attempting to repair the damaged shinyuuchi of Hidagou. Yamiankou attacks immediately, but Yoshimori's kekkai melt on contact with Yamiankou, and his zekkai offers little protection from it. Yoshimori is saved by Mamezo, who uses his extending vine to pull Yamiankou's tentacles away from Yoshimori. Mamezo and Yoshimori run away, leading Yamiankou to a mossy field where Yoshimori hides underground and emerges with a large stake. He insults Yamiankou until it charges straight at him. Yoshimori dodges aside, forcing Yamiankou to crash headfirst into a rock wall, and then pierces its body with the stake, using his zekkai armor for more power. With its vulnerable body pierced and exposed to Hidagou's dying atmosphere, Yamiankou dies instantly. Mamezo later notices a man-made ring on Yamiankou's tail, proof that it was being ordered by humans.

Power & Abilities
Fluid Armor: Yamiankou's soft body is covered by a protective fluid, capable of destroying kekkai entirely and rendering zekkai largely ineffective.

Tentacles: Yamiankou uses its tentacles to grab or spear its prey.