Lucifer had checked already twice the house of William and Karen Johnson before he decided to retreat; there weren't any demons in all Connecticut. He then gave new orders at the ones he saw lingering close just in case, not wanting to make it know that he was protecting the place. He even placed a thin layer of grace on top of the recurrent places Aaron went so he'd know when a demon went closer. He already checked the hospital whenever he visited Aaron.
He was sure that he had smell sulfur on Aaron, it may be a coincidence, but he got angry just by thinking that there could be one trying to lay a finger on Aaron.
