Mion, a female teacher in a stagnant relationship with her boyfriend, gets excited by the robust body of a student's father during a home visit and indulges in carnal desire with him. The student witnesses this lewd scene. Later, threatened Mion complies with obscene orders. Gradually, shame turns into excitement as she craves the student's penis. In their forbidden relationship, Mion exposes her desires. This sight also excites her boyfriend. They expose their twisted lust and affirm their love for each other.
