Sakana (逆名) The name comes from a local custom known as "calling the reverse-name."

(About calling the reverse-name: A "reverse-name" is a deceased person's name spoken backward. It is a tradition born from the belief that saying a dead person's name normally in conversation with friends or family will lead to being cursed or possessed; thus, the name is always spoken in reverse.)

An incarnation of the concepts of corpses, the dead, ghosts, vengeful spirits, death, and murderous intent. He possesses a body colder than a corpse, cloudy eyes devoid of light, a flat and emotionless voice, and an obsessive personality.

He has a terrifyingly obsessive personality; when he finds something or someone he likes, he calls out to them and attempts to kill them to make them his own.

He is fundamentally invisible, and at first, only his voice can be heard. Contact begins with him calling out from the other side of something, such as a door.

If he is behind a door, he will knock and call out like an ordinary visitor.

If he is behind a partition or barrier, he will call out in a voice that sounds familiar yet belongs to a stranger, saying things like "There's something interesting back here, come and see."