My Will Is Yours

This story takes place place post-ESB
Vader can't get over Luke's rejection of him at Bespin: in fact, he refuses to accept it and schemes to have his son at his side by any means necessary. Perhaps the dark magick of a Nightsister can help him obtain what he desires...
What's free will got to do with it?
Snippet:
Anakin Skywalker intimately knew the pain of rejection.
When he had destroyed his former self, Darth Vader had used that pain to his advantage, as a means to strengthen his connection to the Dark Side of the Force and become more powerful. Indeed, it had worked: Darth Vader was the most feared man in the galaxy. He carried out the Emperor’s will for the Empire with an iron fist. Who would dare refuse the Dark Sith’s demands and desires?
Yet Darth Vader once again was in pain from the stinging, humiliating blow of rejection.
This time from his own son.