Because you like Jackie Burkhart in That '70s Show
Did he ever tell you the definition of insanity? Just wait, and this psychopath will do just that. See them in Far Cry 3.
Raiden is an efficient soldier haunted by his repressed past. See them in Metal Gear Series.
A nurturing, selfless, and level-headed leader, Makoto Tachibana loves looking out for his friends. See them in Free! Iwatobi Swim Club.
Mikasa Ackerman is a near-perfect soldier who won't break her stone-faced expression whether she's killing foes or protecting loved ones. See them in Attack on Titan.
Oscar Jarjayes is a sword-swinging, fearless Commander of the Royal Guard who cross-dresses as a man. See them in Rose of Versailles.
Years of brutal winters, foreign invasions, and crippling loneliness have left Russia's mental state far from wholly intact. See them in Axis Powers Hetalia.
Given his ability to wrench street signs from the ground, Shizuo Heiwajima is a useful one to have in dangerous Ikekuburo. See them in Durarara!!.
An infamous vampire, Alucard is a one-man killing machine with a philosophical side. See them in Hellsing.
Eragon is one part brave but three parts fool. See them in Eragon.
Albus Dumbledore oversees the most unsafe school in recorded history, with Dementors and giant arachnids run amok. See them in Harry Potter Series.
Sylar's victims are found all over the country, many with their brains removed. See them in Heroes.
Sasuke's quest for vengeance is above all else. See them in Naruto.