Rio is a so-called returnee who speaks in an atmospheric manner and speaks fluent English. He is a music college student who aims to become a pianist in the future. Her intelligent beauty, supple fingertips, and above all, her outstanding promotions are alluring. She also has a secret fetish! ``Actually...I want you to tie me up...'' Rio's breathing becomes rough even after being tied up lightly, and his masochistic nature is rapidly blossoming...