Because you like The Master in Doctor Who
Davos Seaworth is steadfast, intelligent, and trustworthy, which are hard traits to find in a place like Westeros. See them in Game of Thrones.
Caitlin Snow believes that burying herself in science is the best way to save the day or to mend a broken heart. See them in DC Extended Universe.
Causing mayhem practically since birth, rambunctious Fred Weasley plays pranks on his siblings and avoids school at all costs. See them in Harry Potter Series.
Give in to the dark side with vampire Lestat; it's more fun. See them in Interview with the Vampire: The Vampire Chronicles.
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.
Jack Skellington is a nightmare-man with a soft heart and smooth voice. See them in The Nightmare Before Christmas.
A stylish agent, Agent J would rather improvise than play by the rules. See them in Men in Black.
Egon Spengler prefers collecting spores, molds, and fungus to interacting with people. See them in Ghostbusters.
It's impossible to say whether Winifred Burkle is cuter than she is smart, or vice versa. See them in Angel.
Christine Daae has been secretely taking lessons from a phantom musician. It sounded less creepy in her head. See them in The Phantom of the Opera.