Kaori and Haruka have loved Kokoa like family since she was little. Kaori and Haruka, who have grown up a little by wearing uniforms, come to love Kokoa as a single woman. What is the ending of love that Kokoa, who has begun to climb the stairs to adulthood, will reach... Best friend and best friend, best friend's mother and daughter's best friend, a deep and sweet love story spun out of a forbidden love triangle.
