Recently, Ayano started doing yoga because her stomach has been getting flabby. Her son, who had always been exasperated by his mother's habit of quitting everything after just three days, found himself secretly watching her. Seeing her plump body lightly glistening with sweat stirred an unexpected arousal within him, and he couldn't help but get lost in lewd fantasies. Overcome with desire, he became obsessed with her—and finally took action.