Onna kyôshi-gari

A moonlight skinny-dipping session between two carefree high schoolers leads to a young boy being accused of a violent assault on his female classmate. After throwing a teacher to the ground, he stomps out of the school gates and spends his summer break roaming a beachside town. Falling down a rabbit hole into a dark, oppressive world of sex and violence, he is taken in by a bar-owner and his libidinous mistress. (synapse-films.com)