Written by Tsumuji Yoshimura.

In this world, people are born without gender.

Children's bodies transform into their desired gender when they reach the age of twelve. Until his eighteenth spring, Hinase lived happily without gender. However, the lively Ritsu and the thoughtful Shiori confess their love on the same day! Romance was never on Hinase's mind, so how can they react? Hinase must explore their identity as they reach the threshold of adulthood.

Who will they choose and who will they become?