Rika met her husband at university, where he was her senior in the same club. She fell for him at first sight, and their relationship progressed from dating to living together and finally marriage. They continued having sex almost every day after marrying, but about six months ago the frequency suddenly dropped, and now it may not happen even on weekends. She assumed he was simply exhausted from work until she witnessed something shocking and learned the real reason: her husband was secretly meeting another woman.