Because you like Don Lockwood in Singin' in the Rain

Finn is the world's last human who's "all about" understanding right and wrong. See them in Adventure Time.

It's hard to tell if Dean Winchester cares more about saving the world or his 1967 Chevy Impala. See them in Supernatural.

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.