There is a strange breed of mechanical creators, aptly named "Machines," who will grant their wielders fortune and prosperity, but only on the condition that their host never loves another person for as long as they live. And where a host has betrayed his machine, you are sure to find a member of the mysterious Gari family, wielders and hunters of Machines, in the ensuing carnage….

When Maria, the head of the Gari family, enrolls in Shakunage high school to pursue one such machine, she has a less-than-welcome encounter with a young man named Shizuma, and the two ultimately join forces to pursue the Machines together… Well, sort of. But little do either of them know that their chance encounter has set the cogs of fate spinning rapidly into motion!