Birthright(臍帯)

The film involves a young woman named Mika who watches the married couple, Minoru Takeda and his wife Ryoko and their teenage daughter Ayano from outside their home. Mika approaches Ayano and says she knows a male student who would like to meet her. Ayano accompanies her only to find that this is all part of Mika's plan to get revenge on her birth mother.