Because you like Steve Hale in Full House
Due to his eagerness to hang with his kids and general goofiness, Phil Dunphy comes across as the fourth child of his family. See them in Modern Family.
Hiccup Haddock III may be the only Viking nerd in recorded history. See them in How to Train Your Dragon.
Smart, sarcastic, and loyal, Stiles Stilinski doesn't just want to be the sidekick in someone else's life. See them in Teen Wolf.
Severus Snape is a misanthropic potions teacher with a vindictive streak. See them in Harry Potter Series.
A formerly timid caterpillar, Kurt Hummel is transforming into a glamorous, confident butterfly. See them in Glee.
Emily Fields has been very guarded, careful of whom she trusts and reveals her secrets to. See them in Pretty Little Liars.