Visitor Q (2001) on Netflix

Plot summary

Miki Yamazaki, a prostitute, offers herself to her father Kiyoshi for a fee while he films the encounter for a documentary about Japanese youth. Kiyoshi once reported for television. At home his wife Keiko, a heroin user who also sells sex, is beaten by their son Takuya; he throws things at the walls over a toothbrush, and schoolmates fire fireworks through his window. A man in a red shirt twice strikes Kiyoshi on the head with a rock, then comes to stay at the house. Keiko serves the stranger dinner while Takuya beats her, and neither man reacts. Kiyoshi's co-worker Asako Murata thinks his methods go too far.