Chidori is a moody, antisocial rich girl. After a betrayal by one of her closest friends forces her to attend a new school, Chidori resolves that she will never again allow anyone to become close enough to her that they could betray her. However, when Chidori is forced to attend an annual school trip to a beach resort, her entire world is turned upside down.

There, she meets an odd couple who introduce themselves as August and April. When Chidori is roomed with April, she quickly realizes that she is attracted to the girl. Chidori tries to fight the urge to become more than friends with either one in fear of both betrayal and of ruining their relationship. Soon her fears are forgotten. April and August prove to be the perfect friends and the three grow very close over the course of the school trip.

However, April and August have a secret that could not only tear apart their friendship but entirely destroy Chidori's life. As the pair fall deeper in love with Chidori, they must make an agonizing choice between duty and love...