In her thirties, a NEET with low self-esteem, former honor student and older sister, Tsukino Kasumi (MKON-130)

During his extended holiday, Fu went back to his hometown. His stepsister, Xia, who used to be a top student and worked for a large company, had been staying at home ever since she developed a mental illness due to overwork. Her family suggested treatment, but Fu felt that forcing her to perform would be detrimental. One day, she was suddenly told, "You can't do anything. I'm sorry, I'm such a useless stepsister." Looking at Xia's empty expression, Fu worried that "if left unattended, she might die." Fu desperately tried to think of a reason for his stepsister to live. "There's not much I can do for Fu, but if there's anything, just say so..." So Fu said, "I want to see her breasts." Xia, who had low self-esteem, said, "My naked body has no value whatsoever..." but Fu disagreed, and then started kissing her breasts...