L's successor

L's heir or L's successor is the person to succeed L if anything should happen to him.

Main Article: Wammy's House
Little is known about how one is chosen to be a successor, though it seems that L himself choses. The child is assumed to be a resident at Wammy's House, an orphanage created by L's mentor, Quillish Wammy (aka Watari).

Near and Mello
L has two successors, Near and Mello. It appears that they were chosen at a young age, with Near being thirteen and Mello close to fifteen when they were introduced in the story. Of the two children, only one was intended to gain the title of L, but because of L's death neither child was officially picked. After learning of L's death, Roger proposed to the two that they work together. Near agreed, but Mello found it impossible to work with Near and gave Near the position as L.

Main Article: Death Note One-Shot Special
As shown in the manga one-shot taking place three years after the main storyline, Near remains the current L and solves cases under the L name.

Main Article: Death Note: Another Note
The Novel, Death Note: Another Note greatly expands on information regarding L's successors. Within the novel, two other successors are introduced: B and A. These two are reffered to as the "first generation" of successors, having been chosen before Near and Mello. The first successor, A was unable to cope with the pressure of having to succeed L, and committed suicide. The second, B became a serial killer and was later killed by Kira while in prison.