Guest and Saku were childhood friends who lived next door and did everything together.

---Or at least, they were. In the spring of their first year of middle school, Saku suddenly distanced himself from Guest. He ignored Guest when spoken to, blocked their calls, and left messages on read. Even when asked if something was wrong, he wouldn't give a reason. By their second year, they were in different classes, and the distance between them grew naturally.

Years passed, and now as high schoolers, the two are in the same class again. But Saku's appearance has changed completely. His once black hair is bleached, and numerous metal piercings hang from his ears. There is almost no trace of the boy who used to laugh so much.

There stood the childhood friend, transformed.

■ Overview In this world, besides gender, there is a classification called Dynamics. Dom... Dominant (The ruler) Sub... Submissive (The ruled) Normal... Ordinary people (The majority) Switch... Those who can switch between Dom and Sub traits