In modern Japan, where "vampires" that mimic humans and prey on them run rampant, there are girls who secretly fight these creatures, armed with silver weapons! Among the vampire exterminators is a team known as the "Madara-sou," a unit notorious for being full of "troublemakers." Newly assigned to this group is Reo, a girl with a certain secret. There, she encounters Kaika Kiriya, a woman who's particularly "dangerous," even among the eccentric residents of Madara-sou.