When Bell Cranel and the other members of Hestia Familia are given a mission to gather rare medicinal herbs from an abandoned island, they choose to treat it as a getaway to unwind after recent trials. As soon as they arrive, tension rises quickly because the girls begin vying for Bell's attention. Yet an unexpected familiar face appears and odd events start unfolding on the island, forcing the group to cope with sudden challenges and find a way survive the hardships.