Itachi Uchiha

"Foolish little brother. If you want to kill me, then hate me, despise me. Run, run, and cling to life."
 * -Uchiha Itachi to Uchiha Sasuke after murdering the Uchiha clan

Uchiha Sasuke's brother, Itachi is a wanted S-class wanted criminal.

History
Itachi was the greatest at his academy at age 7, mastered the sharingan at 8, and became a chuunin at 10 years. By the age of 13 he had already become an ANBU leader, and around that same time he murdered the entire Uchiha clan after killing his closest friend and gaining the Mangekyou Sharingan. He left his little brother, Sasuke, alive, giving the last Uchiha the secret to obtaining such fearful power.