Gift: eternal rainbow

A high school student named Amaumi Haruhiko lives in Narasakicho, a town where a mysterious rainbow constantly appears and is connected to a magical wish known as "Gift." This wish is a one-time offering exchanged between two people. As a child, Haruhiko was close to his friend Kirino, but later formed a bond with Riko, a non-blood sister, before they were separated due to financial difficulties. Years later, Riko returns to Narasakicho and enrolls at Shimano Academy alongside Haruhiko and Kirino. The story explores the evolving relationships between these three characters while gradually uncovering the origins of the Gift and the rainbow.