Because you like Ernie in Sesame Street

Helena is a mentally unstable, childish, and completely merciless. And most of all, she's an unstoppable killer. See them in Orphan Black.

Derek Morgan is thoughtful and kind, but he won't say no to knocking the occasional door down when he gets the chance. See them in Criminal Minds.

Liu Kang spends his days training his body and spirit, seeking to become the ultimate warrior. See them in Mortal Kombat.

Jessica Rabbit isn't bad. She's just drawn that way. See them in Who Framed Roger Rabbit.

John Yossarian is trapped in irony as he must be insane to leave the war but if he does try to leave, he'll be deemed sane and will be forced to stay, See them in Catch-22.

Tina Cohen-Chang is a shy loner who becomes a fierce performer on stage. See them in Glee.

The seasoned detectives in River Heights have got nothing on amateur sleuth Nancy Drew. See them in Nancy Drew.

Spyro the Dragon loves getting into trouble around the Dragon Realms. See them in Spyro the Dragon.

Give in to the dark side with vampire Lestat; it's more fun. See them in Interview with the Vampire: The Vampire Chronicles.

As Marlena Rosenbluth is finding out, confidence in the limelight doesn't always translate to power at home. See them in Water for Elephants.

Alex Russo desperately wants to keep her magic – after all, things are so much easier when you can just wave a wand. See them in Wizards of Waverly Place.

Bad-ass Rayne has sworn her life to finding and destroying her vampire dad, Kagan, and killing as many other vampires as she can in the bargain. See them in BloodRayne .