Anego

32-year old Naoko Noda works at a large company in Tokyo. For her younger colleagues she is a kind of role model and a person to solve any kind of problem for them, so they call her "anego", big sister. But inside Naoko is insecure and wanted to marry before turning 30, like most of her colleagues, too. When she meets a good looking man in a train, who saves her from a drunken man she imagines him to be her future husband until she discoveres he has a wedding ring on his finger.
Eriko Sawaki, a former colleague of Naoko appears again to ask her former big sister about problems within her marriage. But the man from the train turns out to be Eriko's husband...