Because you like Bull Randleman in Band of Brothers

When the Sorting Hat touched Draco Malfoy's head, it placed him in Slytherin, a house that has turned out more dark wizards than any other. See them in Harry Potter Series.

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

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.

L is enigmatic, child-like, and one of the smartest people in the world. See them in Death Note.