Tokito Muichiro is 12 years old, he lives in the same house as his twin brother Tokito Yuichiro. On a hot summer night, a demon attacked Muichiro and Yuichiro. Yuichiro's left arm was cut off by the demon, Muichiro panicked and helped Yuichiro up. Muichiro risked his life to run outside to distract the demon, after a while he used an object to hold the demon down to prevent the demon from moving. Muichiro enters the house to find Yuichiro dying. Muichiro falls but still managed to Yuichiro