Because you like Alison DiLaurentis in Pretty Little Liars
Basil Hallward is dominated, soul, brain, and power by Dorian. See them in Dorian Gray.
Given his ability to wrench street signs from the ground, Shizuo Heiwajima is a useful one to have in dangerous Ikekuburo. See them in Durarara!!.
It's easy to see why Poe Dameron would side with the rebellion: he's bad at taking orders, likes to show off, and is committed to the cause. See them in Star Wars Series.
Vincent Vega likes a good steak, a cheap milkshake, and killing a target without anything going wrong. See them in Pulp Fiction.
Chuck Bartowski is a sweet, laid-back electronics store/top secret government employee. See them in Chuck.
Tamaki Suoh is always the star of the scene because he's the one making a scene. See them in Ouran High School Host Club.
A man of the court, Lord Varys knows how to manipulate it better than anyone. See them in Game of Thrones.
After Rintarou Okabe develops the Phone Microwave, some of his fantasies start to seem uncomfortably real. See them in Steins;Gate.
The main priority for Nagisa Hazuki is making sure that everyone has fun. See them in Free! Iwatobi Swim Club.
Point the fun-loving Pippin Took towards second breakfast, and he's one happy hobbit. See them in The Lord of the Rings.
Years of being the less desirable Vargas sibling have given Romano quite an inferiority complex, as well as the temper to match. See them in Axis Powers Hetalia.