A New Life.A 16-year-old boy named Kazuki Muto awakens from a nightmare where he is killed by a monster after trying to save a mysterious girl. At school, a teacher named Mita punishes Kazuki for not having proper school equipment and forces him to stay after school. That night, the teacher reveals himself to be the monster from his dream which really happened, causing Kazuki to experience a flashback where the girl uses a kakugane to restore Kazuki's life. Kazuki is saved by Tokiko Tsumura, the same girl who destroys Mita and explains that the monsters are called Homunculi. These monsters are created from alchemy and can only be destroyed by specialized weapons called buso renkins. Tokiko tells Kazuki to go home while she heads to a warehouse where the Homunculi are hiding. Kazuki ignores her warnings and heads to the warehouse where he activates his buso renkin and defeats the Homunculus leader. The girl introduces herself as Tokiko Tsumura and takes Kazuki as her disciple.