Karin secretly starts working for an escort service to pay her tuition, only to discover that her very first client is her university seminar professor. Holding her scholarship recommendation over her head, he sexually coerces his demure adult student into his forbidden “lessons” under the pretense of consent. He even orders her to wear a vibrator during class, and Karin gradually gives in to the pleasure. But she has no intention of remaining his plaything. “You’ll give me a better grade, won’t you, Daddy?” After being caught in his trap, Karin turns the tables, gets leverage over her professor, and takes complete control of him.