around 20-21 minutes into the movie when she goes out on her walk, she turns from looking at the sky and sees a decaying corpse of a dog with a collar on. it is graphic in nature, very detailed. it is a still shot wirh some dramatic sound cues. the corpse doesn't implu any direct violence though, and is not mangled beyond the natural decay
Not a prison in a criminal justice sense, but a pair of people are voluntarily locked up in a house together for a long period of time and they can't leave
A man and a woman (who aren't in a relationship) are staying in a house together; the man treats her in a very degrading manner, verbally abuses her, shouts at her, intimidates her and on more than one occasion physically abuses her.
Most of the film is the main female character being brutalised and mistreated for spectacle. She is constantly verbally abused, shouted at, smacked around and at one point sexually abused by a (very misogynist) man.
He tricks her into stripping so he can masturbate under the pretense that it’s for the ritual, but it is a lie so it is unconsensual, but he doesn’t touch her.
Her son is dead at the beginning, but the story of his death is disturbing and sad. The plot of the story also follows the mother grieving this death, so it's brought up a decent amount.
The woman vomits near the beginning, after eating a mushroom. Nothing is shown (her back is turned) but sound is heard. The man vomits the same way towards the middle (after he gets confused about which symbol to draw).