At twenty, Shihori married and gave birth to Shiori. After discovering her husband's infidelity, she was forced into divorce. Fearing life as a single mother, Shihori devoted herself to raising Shiori as happily as possible. Her efforts paid off—Shiori landed a job at an IT company and even got married. Since Shiori rarely spoke about romance during her school years, Shihori suspected she might be a lesbian, secretly feeling relieved. But suddenly, Shiori called, inviting her on a trip. It had been a long time since they'd traveled together, yet Shihori casually accepted the offer.