In a world where vicious monsters known as "Mag Beasts" step out of the shadows to kill, Vincent Fuske is a lowly Guardian, failed in battle, trying hard to protect the city from impending doom. While exploring an abandoned ruin, Vincent and his friends unknowingly awaken a Mag Beast and things take a swift and fatal turn for the worst before Vincent discovers a potential link with a special creature named Vira.
Unlike the other Guardians he has the unique ability to enhance Vira’s strength, not through typical training, but through a melding of their forms. By fusing with Vira, he can use her strength, upgrading it with each fusion, rapidly developing a strength and closeness that will unlock Vira’s true form. 06 The deeper the fusion with Vira grows, the stronger the bond between her and Vincent becomes, and the more the transformations are pushing his body and soul.
As Vincent increases in power, he becomes the subject both of human factions wanting to use him to their ends, and horrible Mag Beasts with their own motives. He needs to navigate a world poised on the edge of war, reveal sinister secrets behind the origins of the Mag Beasts, and choose how much he is willing to sacrifice in his desire for power and survival. But after his relationship with Vira deepens, Vincent starts to wonder if he is turning into the very monster he used to battle.
