Haneda Eiko's husband was once kind and gentlemanly before marriage, but recently he has become arrogant and bossy, leaving her completely unattracted. Though she initially worried it might be due to work-related stress, in truth, his true nature had simply surfaced. After confiding in a female friend, she heard stories about infidelity and, driven by a desire for uncharted excitement, chose to offer her body to another man. Meanwhile, Aikawa Izumi married a Thai man and now lives a successful life in Thailand—her husband runs a popular restaurant while she works as a local tour guide. However, his overly gentle and polite affection left her unsatisfied. When she returned to Japan for her sister's wedding, her real purpose was to have sex with a Japanese man, revealing her hidden, lustful side as a married woman, contrary to her demure appearance.