Shiro Mibu is another enigma of the SoulTaker series. He is calm and collected, despite his dangerous lifestyle. He has past ties to the Kirihara, which will someday be revealed. Shiro is very fond of food and can often be seen eating, whether it be hot dogs with hot mustard or ramen noodle soup. He has a habit of making sound effects noises for actions her completes or implies, such as "Ting!" for his metal baseball bat making contact with a enemies weapon, ot "Batatatatatata!" for mock machine gun fire. He is also often seen chewing on some type of weed.

Whether Shiro is a friend or enemy of Kyosuke remains to be seen. He saved him from an insane Hospital Doctor, but Shiro also told Kyosuke that he would not hesitate to use him as a stepping stone to get what he wants.......The destruction of the Kirihara Group.