Light Yagami
The manga series "Death Note" features an extensive cast of fictional characters designed by Takeshi Obata with their storylines created by Tsugumi Ohba. The story follows the novel of a character named Light Yagami, who uses the notebook he found in order to "cleanse" the world of those humans which he deemed unfit for society. A team of professional investigators set out to find out the mysterious killer and arrest him, and thus many other characters are introduced until Light is eventually caught.