Sei, who moved in next door to the Maihara family, runs an esthetic salon in her home. I've been suffering from severe shoulder stiffness lately, so I went for a treatment with my wife... As soon as Sei found out that I was a masochist during the treatment, he revealed his true sadistic nature, and, not minding that my wife was next to him, he teased me and brought me to orgasm. I thought it would be bad to go any further, so I tried to avoid interacting with him, but I couldn't resist her skillful words and sexual techniques, and I ejaculated many times. As I continued to be made to cum, I gradually became addicted to her body, both in Kokoro and in body...