夜神月
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.