After the human colony on the moon was destroyed by disease, Kyosuke Date and his mother flee to Earth- separated from their family. They take refuge in a cathedral where his mother hides as a nun for reasons unknown to Kyosuke. After dangerous people find their sanctuary, his mother stabs him before she herself is murdered.<br><br> Days later, Kyosuke finds himself alive and in the house of a mysterious girl who claims to be his twin Runa- and she is not the only one! Runa suffered a similar fate at the hands of her adoptive mother; however her soul was divided into several pieces making "flicker girls" who are being hunted by the evil Kirihara Group. The reason Kyosuke survived: his body's DNA conformed to the disease and he is able to transform into a fearsome alien mutant known as the SoulTaker.<br><br> Kyosuke begins his battle against a hospital of evil mutants and dangerous corporate assassins in order to save himself and the sister he has never known.