Triloquist (2008)

Triloquist centers on a brother and sister duo and the ventriloquist dummy named Dummy that they regard as a living, breathing sibling. After their ventriloquist mom died of a drug overdose in a seedy Hollywood hotel and they found themselves getting bounced around to varying foster homes, including an uncle who molested the girl until Dummy suffocated him with Saran Wrap, they now find themselves all grown up and seriously screwed up. After Dummy kills a kid on Halloween, sister Angelique places the blame on her simpleminded mute brother Norbert, resulting in him getting sent to a mental institution and her heading off with Dummy to live the life of a psychopathic sexpot armed with a maniacal puppet. This leads to scenes like when she offers oral sex to a guy who turned her down for a job only for Dummy to perform the act on the unsuspecting perv and then biting his genitalia off. [imdb]