12. Roxanne Mesquida and Libero De Rienzo in Fat Girl (2001)
French filmmaker Catherine Breillat has earned a reputation as one of cinema's most provocative crushers of cinematic taboos, and anyone who's seen merely one of her movies knows why. Take 2001's Fat Girl, for instance: Arguably her best work to date, the naturalistic, unflinching look at an overweight teenage girl's coming-of-age features a couple extended sequences of underage sex, acted out by the title character's promiscuous older sister.
With the chubby Anais (Anais Reboux) watching, while totally awake, in a neighboring bed, Elena (Roxanne Mesquida) intensely makes out with a new beau (Libero De Rienzo) before letting him introduce her to her first anal tryst. And the experience isn't a happy one for Elena, nor Anais, and especially not anyone who's able to stick around and watch Fat Girl's most jarringly assaultive moment of a rude sexual awakening.