The story follows a high schooler named Yuuichi Katagiri and his close group of friends who are abducted and forced to participate in high-stakes, manipulative games to pay off a massive, mysterious debt. The series kicks off when the funds for a high school trip are stolen. Shortly after, Yuuichi and his four best friends are ambushed and wake up trapped in a mysterious room with a creepy, doll-like mascot named Manabu-kun. Manabu reveals that one of them put the group into a 20 million yen debt to cover their personal losses. To clear their names and survive, the friends must play a series of psychological "Friendship Games" that test their trust, expose dark secrets, and push their bonds to the absolute breaking point.