The Face Alleys are where you find the Eyeball Boxeffect, and is located at the botttom right of the Nexus. The lonely area is populated by floating picture frames, and its defining features are the various expressions drawn on the walls.
Many walls have mirrors on them, and Usotsuki can peer at her reflection, which shows her with a black hole for a face. This has some implications regarding her self-view. Mirrors can be broken with the Nail bat, and if the player hits enter twice, mirrors can teleport Usotsuki around.
Reflected in a certain mirror is a doorway that is hidden from the players view. This door takes you to the second part of the Painted Hall which in turn leads to the White Plains. Going inside a face's mouth leads to the White Tiles Path, which connects to Red Bubbles Maze.