Because you like First Doctor in Doctor Who

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 .

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