I'm stuck. I have slain the wolf boss in the fire level. I have also lay with it. But when I go back to the room the winged lady says the same thing and the book says I need to unlock the essence first. What am I doing wrong? 

Edit: nvm I figured it out. The book on the bedside table was showing the first page (the training dummy), I didn't realise you're supposed to scroll up or down I couldn't see any screen prompts for it (android version).