The Real-Life Lorraine Warren's Account
There are two sources that communicate a similar haunting experienced by the real-life Lorraine Warren. The first comes direct from The Conjuring 2 director James Wan. While doing press rounds, Wan recalled how Warren described the shape of an entity that had haunted her once upon a time. "From talking to Lorraine in passing, she mentioned a spectral entity that has haunted her in her house," he said, "And it's this swirling tornado vortex with this hooded figure in there." This description is actually how Wan got the idea for the look of his creepy nun in the first place!
In another interview, this time a 2013 chat with the The Telegraph, Warren recalls the only time she was ever scared during her work with paranormal and supernatural forces. "I have been thrown up in the air by the power of a demonic spirit," she said, "and it's not easy to go back to your work after that. But you have to." While it's not clear if the entity Wan described is the same as the one that threw her, it's easy to see where "Valak" from The Conjuring 2 originated. And speaking of Valak, we've arrived at the next piece of The Nun's puzzle.