Hitoshiki Zerozaki

The culprit of a string of Kyoto serial killings. He first encountered "I" on Friday the 13th, initially wanting to make "I" his next victim, but "I" fought back. As he was going for the kill against "I", "I" was prepared to strike out Zerozaki's eyes, but Zerozaki stopped his attack, impressed. They talked for some time afterwards and became something like friends.

He has a tattoo on the right side of his face, white-dyed hair, three earrings on the right ear and one cellphone strap on the left ear. About 150cm, very short for a guy. Zerozaki is the mirror self of "I", hence the other way around, too, acting as his foil. He always wears a vest full of knives and is skilled with them.

In the second volume, he faced Aikawa Jun in combat, but admits he was no match and had to flee for his life.