Because you like Leonard "Bones" McCoy in Star Trek

Basically a giant pillow come to life, Baymax is a medical robot created for the sole purpose of helping people. See them in Big Hero 6.

The Terminator is an emotionless killing machine who won't stop until he's changed the future. See them in The Terminator.

Make sure not to anger the Hulk or else he will transform into a giant green monstrosity and smash anything in his way. See them in Marvel Cinematic Universe.

Rukia Kuchiki is a cool and collected warrior who has trouble opening up to anyone. See them in Bleach.

Suzy Bishop is only 12, but her withering stare and withdrawn personality are enough to make anyone wilt. See them in Moonrise Kingdom.

Daring on a bike but haunted in his personal life, even Johnny Blaze isn't fast enough to outride his past. See them in Ghost Rider.

The last war left his economy devastated, and now Germany is engaged in another war and stuck with two barely trained allies for help. See them in Axis Powers Hetalia.

With his perfectly combed hair and flashy military outfits, France can charm the pants off of anyone—well except his fellow nations, it seems. See them in Axis Powers Hetalia.

Raz is a 10-year-old boy who mostly stays in his own head, which makes sense since that's where he is strongest. See them in Psychonauts.

High school is Hell, so Allison Reynolds spends her time giving herself tattoos with ballpoint pens and shaking dandruff out of her hair. See them in The Breakfast Club.