They can be our biggest annoyance, our biggest help, or just there to be downright adorable. A familiar is someone that follows the protagonist around during the game kinda like a pet/companion/sidekick (i.e Midna, Pikachu, Daxter)
I like Midna
She was kinda cute, she was badass at times, and her true form was gorgeous. That part when she first speaks in her human form puts a grin on my face.