Sefure no Hinkaku: Ketsui

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.