47-year-old Sachiko Hayashibara is a homemaker celebrating 23 years of marriage. She admits she never particularly enjoyed sex in the past, and even after marriage, there was a mismatch in sexual desire with her husband, rarely exceeding once a month. Surprisingly, it was only a year ago that she first discovered the pleasure of sex. One day, half-skeptical, she tried a mysterious potion her husband had purchased from a questionable online site. To her astonishment, she was overwhelmed by an unprecedented sensation and experienced her first ever orgasm. Since then, she has deepened her understanding of sexual intimacy and compatibility in ways she never imagined.