Shin are beings of the Shadow World. Their opposite and counterpart are the Rei.
Shin are shadow beings who have obtained power by contract with a Shin King (ie. Shirogane). They are humans with dark factor who have decided to serve the King they are contracted to. When a person accepts the King's contract, they become a "child" to that King and must obey the King's every command.
Shin Kings are also shadow beings. Their factors are dark and can command kokuchi along with their "children". Kings can accept up to five "children". When a King dies, their children die with them.
Powers and AbilitiesEdit
Generally, Shin possess abilities that are beyond human capabilities; such as athletic and fighting abilities and they do not age physically. They also seem to gain a single unique skill, such as Lulu's absorption of life-energy, upon becoming a shin. Usually in different classes from Kokuchi, Children, Kings, and Direct Kings.