Gift: Eternal Rainbow

Amaumi Haruhiko is a high school student at Shimano Academy in the town of Narasakicho. The town is watched over by a mysterious rainbow, said to be connected to a magical wish known as "Gift"-a once-in-a-lifetime exchange between two people. As a child, Haruhiko was close with his childhood friend Kirino until Riko, a non-blood-related sister, entered his life. The two grew very close, but they were eventually separated when Haruhiko’s father could no longer support them both. Years later, Riko returns to Narasakicho and, alongside Kirino, enrolls at Shimano Academy with Haruhiko. The story follows their relationships while gradually uncovering the truth behind Gift and the rainbow’s significance.