I mean, hard to say without actually seeing the pictures and knowing the person. There's a difference between
1) Finds you out each time you sleep at work, takes stalkery pics where she sneaks up close to you to take close-ups and trying to get some kind of sexy shots that she then prints out, draws hearts around your face and plasters on the walls of her apartment & uses as the desktop background image on her personal PC
vs.
2) something more innocent. Like she sees a friend coworker sleeping at work, maybe thinks that you look funny with your mouth open or something and takes a quick shot and then shows you with a "lulz, look at what you looked like when U were sleeping", "haha, caught you sleeping at work again", and then forgets the pictures are even on her phone afterwards.
I've had people take pictures of me sleeping and I've personally taken pictures of sleeping people. The situation has usually been something that is just funny or maybe I/they have looked funny while sleeping for some reason or just someone sleeping at a more public place and that makes it more or less picture worthy.