Path of the Beast(1980)

17 year old Saki lives in a run-down shack with her mom, who survives by pushing a food cart from dawn to dusk. Saki has dropped out of school, and when she's not helping her mother selling noodles in the streets, she's playing flesh-games with boyfriend Sotoo. In her spare time, the girl also entertains a truck driver named Ataru. She believes her promiscuity is a trait inherited from her mom. Determined to improve her lot in life, Saki decides to stop seeing the two guys.

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