The Pain Demon is a demon, and a canon character in Yandere
The Pain Demon has white skin. His eyes are entirely black. He has stubs for arms, and he is bent forward. His mouth is contorted.
To complete the Pain Demon's ritual, the player must follow a number of steps.
First, they must get the ritual knife from the Occult Club and kill 5 students with it. Then, they must dismember the bodies outside of the summoning circle with the circular saw. Finally, they have to place the arms inside of the summoning circle.
If done correctly, Yandere-chan will levitate, and her eyes will become entirely white. Large white hands will surround her. These hands will dismember any NPC besides Rival-chan, Genka Kunahito, and other non-interactive characters.