I didn't personally experience it but the walker I was with told me about this. After our session, I left earlier and the walker stayed in the room as there was still time left to consume for our room. She took a nap after I left. She told me that she had a nightmare when she was alone in the room. She said that she looked at the mirror and instead of seeing her reflection, she saw an old woman staring back at her. Spooked, she immediately dressed up and left the room.
This was in a room in Sogo North Edsa, the one in front of Trinoma.