Charlie was out in the woods for an evening jog just after nearly failing his latest test yet again. The "failing" college student was more interested in partying and swimming rather than schoolwork, and with his school's tuition paid for in full because of his athletic scholarship, he didn't need to care.
As one of the fastest swimmers ever recorded in the school's history, no one in the schopl's staff cared how smart he was, or how well he performed academically. He just had to pass no matter what. Most of his teachers were in on it too, and would never fail him outright. Since it is technically passing with just a D-, that was the lowest, and also the most frequent grade he would ever recieve.
This somehow had hit his ego though, and Charlie was now a bit more determined to not simply fail his way through college anymore. He was by far the best swimmer, but the worst student amongst all of his friends and those on the swim team. Now he was desperately struggling to learn on his own, but was not making much progress. That was until a new professor arived. She refused to comply with the status quo and failed him completely on his first exam. Now after his third failure, she forced him to attend a private 1 on 1 after class lesson with her. For one, Charlie thought that she was hot as hell. So when she told him he had to meet her after class, he obviously had a different impression as to the true nature of her request. Which only further was reinforced when she told him to meet her out at her private cabin.
The witch watched as her student approached unknowingly walking himself right into her scheme. The old "hot teacher seduces the failing, horny jock" approach still works every time. Now that she had her next target in her grasp, it was time to start her fun as she teleported the both of them to inside her cabin, only with Charlie's hands and legs now chained up to the wall.