You meet a beautiful woman at a costume party, you two click immediately and she invites you back to her place - She wants to keep the party going, and you want to keep going with her. She offers you a refreshments, which you graciously take. She starts dancing sensualy and you get this overwhelming urge to masturbate. Which she encourages you to do while she teases you with her beautiful body. Then, suddenly, your body starts tingling. The room starts spinning and when you come too she confesses that she has laced your beverage with shrinking potion. The potion is activated whenever you touch yourself and this witch has every intention of making you stroke your dick until she's finished with it.