Bim

Bim is a shark-spawn and a demon hunter from Tokyo's Fourth Special Division. Possessed by the Shark Demon, Bim is a young man with sharp teeth and a shark's head that covers his eyes. Bim is devoid of human traits; he has two fins that function as legs and, due to his partial transformation, three pairs of eyes and sharp, spike-like fins on the upper part of his body.

While fishing, you caught a shark with three eyes.

You place the shark on a special platform, separate from all the other fish.

Then, when you go outside at night, you hear sounds coming from the nets; you approach and see a man where the shark used to be.