I have a friend that did it in her powder room.....her's was "a kiss is just a kiss". Her sink and toilet were black, the walls were stark white, and the lettering was black. She then took pictures of all her friends and family smooching....printed them in black and white and framed them in black. Did the pictures in all different sizes. Her towels were red and black and she had some other stuff in there that was red, black and clear crystals. (she's single)
It looked great and everyone always came out of the potty commenting about the pictures and wanting theirs up on the wall if they weren't already.