The canine companion to main character Fumiki. He was hiding in an abandoned building where Fumiki found him. 23 listens to his poetry and can even speak like a human. His bond with Fumiki makes him believe than all man is good.
Has the appearance of an (already extinct) Japanese wolf. He can grow spikes from different parts of his body, usually his forehead. He has the number 23 tattooed on his ear, which made Fumiki call him 23. He is able to recover quickly from serious, even fatal, wounds. He can pass on his powers to anyone who happens to touch his blood.
He has two known brothers: Zero and the second unnamed inugami with an incomplete body.