Thirty-six, eighteen. The two girls are just so perfect. In this world where people come and go every moment, they rely on each other and support each other. They are obviously so close, but yet they are alone with each other. No one knows how these six years have passed. They don't know how many six years they can go together, and they don't know whether they will be separated from each other in the next six years and become kapok in their memories.