Shintaro Kuga , also called "Shin", is the main villain and penultimate boss of Castle of Shikigami II.
The older brother of Kohtaro Kuga, Shintaro have always pursued power, believing himself to have the right to rule the world. He became the head of the cult called the "New World Order," using the cult to summon the Castle of Shikigami on Japan to attain god-like powers, having summoned all other bosses to protect the castle upon sensing the presence of his brother.
Shintaro is capable of using all shikigami powers of the playable characters (except Kohtaro), combining them on his various attacks. Upon being defeated, Shintaro vanishes, transforming into World Order.