The Proto effect changes Usotsuki's hair to green and her dress to grey. It is purely cosmetic, but can cause the woman who makes up half of the Faceless Couple to follow you around.
- Visit Madotsuki's and Urotsuki's room in the Chess Board at least once.
- Turn the chess board black by either triggering it randomly by stepping on a tile or passing through a pair of columns.
- Go between the two queens in the north area where the reference room used to be.
- Make sure no effect is in use and interact with the mask behind the giant spike that has replaced the room.
- Follow the path into a room that appears to be Usotsuki's room. Take the book on the desk to aquire the effect.