A boy and a girl are forced to join hands for all eternity!? In a land ravaged by an epidemic known as "Troy", the only people with healing arts capable of stopping the seizures caused by the disease are the Sisters. Although they have a high resistance to the disease, they are searching for a person who is truly immune, so that they can find a cure. The main character is Sister Elraine, one of the Sisters who becomes infected with Troy. But, when she touches Kiri, a seemingly ordinary boy, her seizures stop. Could he be the one!? In volume 1 is included the oneshot Island: A story that takes place on the day Aira turned 14, and learned the devastating truth about the island she lives on, which is completely surrounded by a huge wall...