Because you like Rust Cohle in True Detective Season 1
Deadpool thinks life is an endless series of train wrecks with only brief commercial-like breaks of happiness. See them in Deadpool.
Poison Ivy is a seductive, venomous botanist laments the fact that there are so many people to kill, yet so little time. See them in DC Extended Universe.
Hawkeye is most comfortable perched above the action, keeping an eye on everything and using a well-timed arrow to save the day. See them in Marvel Cinematic Universe.
Jessica Rabbit isn't bad. She's just drawn that way. See them in Who Framed Roger Rabbit.
Marie Antoinette may be a fun-loving queen who has it all, but her husband doesn't know how to have sex, and an angry mob wants to cut off her head. See them in Marie Antoinette.
It turns out the girl of your dreams just might have dreams of her own. See them in (500) Days of Summer.
Vanellope von Schweetz is princess of the Sugar Rush game who could care less about being royal. See them in Wreck it Ralph.
Stuck somewhere between life and death, Talion is motivated by one thing only: vengeance. See them in Middle-earth: Shadow of Mordor.
His murderous megalomania aside, Loki is quite charming. Just don't mention his strapping older brother; he's a tad jealous. See them in Marvel Cinematic Universe.
Lady Bird's heart is in the right place, usually, but even the purest of people can fall sway to the havoc-wreaking traps of senior year. See them in Lady Bird.
Severus Snape is a misanthropic potions teacher with a vindictive streak. See them in Harry Potter Series.