Amidst a whirlwind of a married woman's shame and taboo desire, a request arrives to fulfill the husband's cuckolding fantasy. Mitsuha, married for four years, is a quiet woman harboring secret desires for infidelity and growing bored with routine sex. Approached by the organizer of a swinging club and persuaded by a man, she agrees on the spot to be taken. Initially resisting as she receives foreplay, she soon cries out once the man's cock penetrates her, climaxing repeatedly as she rides him in the cowgirl position. Afterward, she's tormented with sex toys, experiencing multiple consecutive orgasms. Each thrust drives her to boldly beg, "Fuck me harder," writhing passionately—her intense arousal evident even as she cums.