A

A is mentioned briefly once in the book Death Note: Another Note. A was the original successor to L, and lived at the orphanage known as Wammy's House. A committed suicide after the pressure of having to succeed L became too much for him to handle.

Trivia

 * In the film L: Change the World A's name was not seen on L|L's computer screen.
 * It is mentioned in one line of the novel that A is male.