Ki wo Tsuke na yo, Onee-san.
気をつけなよ、お姉さん。
Tae Honda, an office worker, goes swimming at a community pool but suffers a cramp and nearly drowns before being rescued by Mai Igarashi, a tall and attractive woman. Tae is drawn to Mai, who appears afterward carrying an elementary school backpack, hinting at an unexpected aspect of her life. The story includes four additional chapters.
