Nendo has a simple way of thinking, but because of it, Saiki is unable to read his mind. Because Saiki is unable to detect Nendo's presence, Nendo is the only person who is able to sneak up on Saiki and making him think he will someday be a dangerous foe. Nendo believes he is a friend of Saiki, but this is definitely not the case as Saiki despises Nendo. Saiki would often compare Nendo to a bug, as bugs are one of the few animals that Saiki cannot read the minds of.

Shin's mask is shaped like a human heart, although he usually wears it backwards with the front of it facing backwards and two eye holes cut out of the back. Without a mask he is blond with blue eyes, and wears glasses. He is usually in a suit with an un-tucked white shirt and sneakers. His tool of choice is a hammer, as well as his magic smoke that allows him to dismember and dissect people without them physically dying. Despite being a hitman Shin believes in fair fighting and refuses to use his magic abillity's on people who cannot use magic, resorting to his hammer instead. In contradiction to Shin's controled and content nature he is very blood thirsty for competition. as shown in the first chapter, he gets thrilled when En assigns him and Noi with the task of killing Kaiman and Nikaido.