A mannequin lives in a shop window in a desolate street. Every night she comes to life and plays with the display in the window. For example, if she is dressed as a rock star she strums on a guitar, if she is dressed fashionably (for example in a black dress) she will pout at a mirror. I also thought she could have a toy dog at one point and be upset after the window change and the dog isn't there.
She has no knowledge of the outside world. Until...
One night, a young early twenties couple have been on a night out and stagger past the shop when the mannequin is awake. They both frighten each other, but place their hands on either side of the glass as if they would touch.
When the mannequin goes back to sleep and awakes the next night, she wants to explore the outside world and the story changes to her trying to escape the window she is held in.
I am unsure of the ending yet, whether or not she succeeds, because she will just turn back to sleep for the daylight hours and this may make it a sad ending. Otherwise, she could be joined by another mannequin, possibly male so that she herself becomes part of the couple she sees through the window.