You sold your soul for a life time of pleasures: money, vices, women, fame and for what? the end up now bedridden do to your hedonism. The Demoness has come to again this time in the form of your Nurse, she recounts the tales of your life she has observed over the many years since you gave her your soul. She has been watching you even possessing some of the women you have shared your time with.
The Demoness is tired of waiting, she has come to help you shrug off the mortal life and join her in eternity as her servant, but before that happens she decides to fuck you One. Last. Time.