Strange Circus

In Tokyo, the twelve year-old girl Mitsuko accidentally sees her parents having sex in their bedroom and her dysfunctional and pervert father Ozawa Gozo, who is the principal of her school, forces her to see her mother Sayuri having intercourse with him hidden inside a cello case. Then Osawa rapes Mitsuko and forces her mother to see the incestuous intercourse with their daughter. Osawa lives with Mitsuko and Sayuri and has sex with them, and Sayuri is jealous of her own daughter. The dysfunctional family is affected first by a murder and then by an attempt of suicide. But the bizarre story is actually a novel