??? (Majora's Mask)

is a character in.

Biography
??? emerges from the toilet of the Stock Pot Inn at midnight asking for paper, remaining until 6 am. Link can give it any item made of paper, such as any of the Title Deeds, the Letter to Kafei, or the Special Delivery to Mama. By doing so, ??? will reward him with a Piece of Heart.

Trivia

 * The concept of a hand in the toilet is based on Japanese ghost stories where a hand grabs from beneath the toilet whenever someone sits in the bathroom.
 * ???'s sound clips are the same as that of Mikau's when Link first meets him at Great Bay.