i.e. what experiences have you had/has someone you know had who told you about it?
My thinly-veiled's mother's had quite a few experiences like having her hair pulled by invisible hands and waking up unable to move (this one was probably sleep paralysis).
The other night I saw some strange black shape cross my path really fast. It was blurred, almost like it wasn't there so I couldn't make out what it was. Probably a shadow tbh.
Anyway, tell me your stories.