Bookstore Dungeon

All I remember now, is that I was with someone in a bookstore, and we were trying to find where all the children's books are. I wanted to find a rare children's book, something like "Horton Hears a Who" or something like that. We looked through all these old, dusty books everywhere, that were in no order whatsoever. They were stacked on top of each other. So I went up to some guy and asked where the rare books where - he pointed to this woman and said it was "through her mouth".
So she opened her mouth, real wide, to the point of it so wide that a human body could fit through there - it basically became a tunnel. I looked in her mouth and said "I can't fit in there" and I was scared to death because it was all dark and red.
So my friend jumps right in and I hear him slide through this long tunnel and land somewhere. I put half of my body in and yelled "I'm not going to fit" and tried to get out. She closed up her mouth and said I could take the stairs.
So I took these long flights of stairs, down to a dark basement with all these people sitting against a wall, handcuffed. A woman had a whip, as she walked back and forth in front of them, telling them the rules on that we could look at the books, but couldn't touch them.

Reminded me of "Nightmare on Elm Street Dream Warriors" movie, where Freddy opens his mouth so wide that a person could fit through it.