Because you like Katara in Avatar: The Last Airbender

The vampire that killed Zero Kiryu's family also infected him, and he starts to crave blood, much to his horror. See them in Vampire Knight.

Clarice Starling is patiently working with one serial killer to stop another. See them in The Silence of the Lambs.

GLaDOS will supply the food when you get together: a delicious cake. Of course, it could just be a trap so she can kill you. It’s hard to say. See them in Portal Series.

The ever-cheerful Tonks can change her appearance at will, but she can't seem to get rid of her clumsiness. See them in Harry Potter Series.

David Rose likes his rose chilled, his linens pressed, and his family quiet. See them in Schitt's Creek.

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!!.

Joyce Byers isn't crazy. She's just speaking to her missing son across dimensions using Christmas lights. See them in Stranger Things.

People think Karen Smith is a dumb blonde, but she disagrees and is proud she can predict the weather with her breasts. See them in Mean Girls.

Donna Carmichael is a free-spirited single mom and gracefully aging hippie. See them in Mamma Mia!.