Because you like Alucard in Castlevania
The Ice King is lonely and looking for a princess to sweep him off his feet. See them in Adventure Time.
It's time somebody has to take over. It might as well be Fish Mooney. See them in Gotham.
Mikey Waters would rather sell his body than rob anybody. See them in My Own Private Idaho.
Mike Ehrmantraut is rutheless, merciless, and probably the most endearing hitman you've ever met. See them in Breaking Bad.
Catherine Linton was once spontaneous and rowdy but ever since marrying the wealthy Edgar, she has morphed into a boiling pot of emotional outbursts. See them in Wuthering Heights.
Greg Heffley will be famous someday, but now he's stuck in class with morons. See them in Diary of a Wimpy Kid.
Rupert Giles is a librarian on the outside, fearless evil-fighter on the inside. See them in Buffy the Vampire Slayer.
Lucille Bluth doesn't understand the question, and she won't respond to it. And you're probably better off. See them in Arrested Development.
If you died and came back to life, and then died more times and came back, you might stop battling evil mutants. Not Jean Grey. See them in X-Men Series.
Don't ask the ruthless queen of the Tokyo underworld any questions unless you're fine with losing a limb. See them in Kill Bill vol. 1.