At a high school reunion, now-stylish, confident, and urbane lesbian designer Miwa crosses paths with ex-girlfriend Ririko. The "one that got away", a powerful formative influence and holder of all her firsts, is somehow now a meek OL (secretarial worker) happily chirping about her upcoming engagement, cooking classes, and plans to become a stay-home mom... plain and boring. As Miwa reminisces about their past love, lingering affection, jealousy, and resentment clash inside. Was the big love of her life just a "youthful mistake" for a bi-curious classmate that seduced her out of boredom? Should Miwa still care? Does Ririko? Alternative Name: Kaikou Effect