36 Fillette (1988)
36 Fillette (known as Virgin or Junior Size 36 in English) is a 1988 French film starring Delphine Zentout and Oliver Parniere, directed by Catherine Breillat. It is the story of a sexually-curious and rebellious 14-year-old (played by 16-year-old Zentout) who has an emotionally-charged and dually-manipulative relationship with an aging playboy. Breillat is known for films focusing on sexuality, intimacy, gender conflict and sibling rivalry. Breillat has been the subject of controversy for her explicit depictions of sexuality.
More at Wikipedia.