Because you like Martha Jones in Doctor Who

Hotheaded and arrogant, Kaneda is nevertheless fiercely protective of the biker gang he leads. See them in Akira.

Optimus Prime is a shapeshifting sentient robot leading a team of robots to stop evil from taking over. See them in Transformers.

Thankfully, Jenna Hamilton has her sense of humor and friends to get her through the endless torture that is high school. See them in Awkward..

Sarah Ashburn lives life by the book and has trouble getting along with anyone who doesn't do the same. See them in The Heat.

Annie Walker can bake a beautiful cupcake, but everything else in her life is a mess. See them in Bridesmaids.

Faith balances her adventurous thrill-seeking attitude with a righteous passion for justice. See them in Mirror's Edge.

Kevin Khatchadourian is a disturbed, affect-less teen on a dark path. See them in We Need to Talk About Kevin.

A bookish know-it-all with a bossy streak, Hermione Granger always stands up for what she believes in. See them in Harry Potter Series.

With great power comes great responsibility, but Peter Parker always seems to get the short end of that bargain. See them in Marvel Cinematic Universe.

What Ron Weasley lacks in motivation and book smarts, he makes up for in loyalty and street smarts. See them in Harry Potter Series.

As Jane Villanueva grapples with a truly unexpected pregnancy, she realizes that her life is "now the stuff of telenovelas." See them in Jane the Virgin.

The adventurous daughter of Port Royal's governor, Elizabeth Swann would rather conspire with pirates than sit pretty in her corset. See them in Pirates of the Caribbean: the Curse of the Black Pearl.