Rin's mother, Rin, trains her son Yoshiyuki to become an excellent lawyer like her late husband through a Spartan education. However, while Yoshiyuki's grades do not improve at all and stress accumulates, Rin himself is frustrated with her and immerses herself in her masturbation. Rin gets impatient when her son's friend Kenta sees her like that. However, she finally explodes the carnal desire that she had suppressed with her reason for his erect cock. And while scolding him, she begins to play with her erect cock.
