Strange Circus

Mitsuko is forced to watch her parents lovemaking by her perverted father and her domineering mother, who imprison her in a cello case employed with a peephole. When Mitsuko’s mother apparently dies, her father forces the girl to be the victim of his incestuous desires, which drives her to attempt suicide with a leap from a height...yet all of this is apparently just the new novel being penned by reclusive, wheelchair-bound author Taeko (Masumi Miyazaki, who also plays the mother). Or is it? (official distributor synopsis)