Called to mediate a married couple's argument, Mizuki finds herself listening to the wife's complaints about her husband's chronic cheating—his insatiable libido driving their relationship to the brink. Frustrated, Mizuki snaps back, blaming his huge cock for attracting women uncontrollably. Losing her temper, she challenges him: "If you've got such a convenient big dick, let's see it right here, right now!" But when the husband, insulted by her mockery, reveals his shockingly massive cock, Mizuki's body betrays her with sudden arousal. Her anger quickly turns into obsession, demanding proof of his infidelity in increasingly intimate ways. Will this confrontation destroy the marriage—or push it into forbidden depths?