Determined to make his beautiful aunt his own, an adult nephew makes an aphrodisiac from instructions found online. When he stays at her home that summer, he secretly adds one drop, then two, three and four, increasing the dose little by little. Her body grows hot, her breathing turns ragged and she twists with desire until she no longer seems rational. On the tenth day, she finally loses control and attacks him herself, then becomes his obedient personal fucktoy.