Overview:

A female college student is masturbating by imagining many things while watching a movie: imagining sex between a sister-in-law and her brother-in-law, imagining sex between a daughter-in-law and her father-in-law, etc. While she was masturbating, she moaned loudly and was caught by her stepbrother. The woman's body gets hot and cannot hold it, so she seduces her stepbrother.