In Falsus is set in a near-future world and follows the perspectives of multiple protagonists: 5 troubled high school girls born under bleak circumstances, and bound around their necks by mysterious collars. In their world, all people wear these devices for unspoken reasons, but they create a common ground for everyone: by displaying a person’s emotions, and their deceit. At the start of the tale, the 5 girls are each compelled to join a strange organization, but what seemed to be at most an unusual scheme quickly takes a stark turn.