36-year-old Shoko Morimura (Aika Yukihira) is raising her daughter on her own while working as a temporary worker. At a high school reunion, she reunites with her first love, obstetrician-gynaecologist Kitada Kazuki (Sho Aoyagi), and has a one-night stand with him. Shoko is once again excited, but becomes upset when Kazuki proposes that she become his "sex friend." Part one of a two-part film adaptation of the popular manga by Yoriko Minato. Directed by Hideo Jojo On the Edge of Their Seats, the film depicts the emotions of a man and woman who spend the night together at a class reunion.

Shoko Morimura (Aika Yukihira) is a 36-year-old single mother who has been in a "friendship" with Kazuki Kitada (Sho Aoyagi), whom she met again at a high school reunion. For some reason, a 17-year-old girl, Saki Yamada (Akari Takaishi), whom Kazuki was taking care of, grows jealous of Shoko and causes an incident. This leads to a break-up, and Shoko is disappointed in Kazuki's defense of the young Saki. Second part of a two-part film adaptation of the popular manga by Yoriko Minato. Directed by Hideo Jojo of On the Edge of Their Seats fame.

Third chapter in the "S-Friends" series. Shoko Morimura works at a mail-order company and raises her only daughter as a single mother. She and her first love, obstetrician and gynecologist Kitada Kazuki, have rekindled their friendship and are having intense trysts. While on a remote island in the countryside, Kazuki finds himself practicing medicine, and as he looks down on himself, he begins to imagine a future with Shoko. Moved by Kazuki's feelings, Shoko prepares to take a big step toward happiness together. But just as they are about to take their first steps, her ex-husband, Hiroshi, turns up, stalking her and plotting to drive a wedge between them.

Fourth chapter in the "S-Friends" series. After a shocking incident, Shoko breaks up with Kazuki and begins having one-night stands with various men. Meanwhile, she gradually becomes attracted to her colleague, Hasegawa Sakutarō. Meanwhile, Kazuki, who lives on a remote island in the countryside, meets Kazebuki Mei, a writer who wanders from place to place like a rootless wanderer, and begins to ponder the concepts of love and life. Shoko and Kazuki spend their days apart, without contacting each other, until one day they are reunited.