Because you like Leo Bloom in The Producers

Severus Snape is a misanthropic potions teacher with a vindictive streak. See them in Harry Potter Series.

After surviving consecutive fights-to-the-death (damn you, President Snow!), Katniss Everdeen is thrust to the front lines of a real war. See them in The Hunger Games .

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.

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.

Castiel might be an immortal angel, but the human world is still more than a little confusing. See them in Supernatural.

A wildly brilliant detective, Sherlock Holmes can figure out everything except how to interact with other human beings. See them in Sherlock.

Both intelligent and empathetic, Remus Lupin is worn down by the weight of a secret. See them in Harry Potter Series.

A dreamy space cadet, Luna Lovegood has never met a conspiracy theory she didn't believe in. See them in Harry Potter Series.

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.