It is not actually a manga, it's a guide to Death Note. It has profiles of the characters ETC.

Well, there are alot of characters, but the main ones are: Light, L, Near, Mello, Ryuk and Misa.

12 manga and 1 book about the characters

there is also a novel called 'Death Note Another Note: The Los Angeles BB Murder Cases'

They are characters from a smash hit anime series known as "Death Note".

Light Yagami from the anime Death Note. He started out good then turned evil because the power of the death note went to his head. Then he thought he was God.