In Chapter Seventeen of The Lightning Thief, Percy, Annabeth, and Grover are wandering around West Hollywood in search of DOA Recording Studios (the location that holds the entrance to the Underworld).
After a run-in with a group of wealthy kids with knives, the trio runs into a store called Crusty's Water Bed Palace. There they meet Procrustes (Crusty for short), who invites them to try out a few of the water beds. Annabeth and Grover...