Polar Opposites

Some pairs of heroes, whether friends of relatives, have opposing personalities, being Polar Opposites. Some pairings are so polar, that they can lead to Forbidden Friendship.

Examples

 * Luke Skywalker is a blonde, blue-eyed, calm, mild-mannered, naive, mystical, religious Jedi Knight. Leia is a brunette, brown-eyed, quick-tempered, sharp-tongued, worldly-wise, shrewd, practical politician. Interestingly, they parallel their parents' personalities from the Prequel Trilogy, with Luke taking after their mother Padmé, while Leia takes after their father Anakin.
 * Annie James and Hallie Parker are completely different. Annie is calm, reserved, and rather uptight while Hallie is relaxed, loud, outgoing, and a big eater.
 * Quest for Camelot has the serious and snooty Devon and the boisterous, fun-loving Cornwall. Unfortunately, they're not only Polar-Opposite Twins, they're also Conjoined Twins, and they're unable to use their shared body to fly or breathe fire until they learn to get along near the end of the movie.
 * Hiccup befriends a Night Fury dragon which he names Toothless, despite humans and dragons being natural enemies.
 * Woody, an old fashioned cowboy doll, is a polar opposite to Buzz Lightyear, a modern day Space Ranger figure.
 * Tod, a wild fox, is a polar opposite to Copper the hound dog, despite being canine friends.
 * The Beast, an aloof prince, learns to love the bookish Belle.
 * Spike the Dragon is polar opposites with Twilight Sparkle, a pony who raised him dearly.
 * Aladdin is a poor boy from the streets, in love with Princess Jasmine.
 * Tai Kamiya thinks of himself, as his sister Kari thinks of others, so much in fact, that the Digidestined needed her help to begin with.
 * Timon always takes things literally, while Pumbaa knows better about some facts.
 * According to their personality ingredients, Blossom has the smarts, Bubbles has innocence, and Buttercup has toughness.

Quotes
"Homer: Ned, I never thought I'd say this, but we make a great team. (Flanders: Us? A team? As the salad said to the soup, I'm all mixed up.) Homer: We should be bounty hunters together.  You're kind and smart.  I'm cruel and strong. Together, we're nothing.  But together, we're the perfect bounty hunter."

- Homer Simpson, suggesting a bounty hunter partnership with Ned Flanders "My brother and I had a give-and-take relationship. I would give, and he would take."

- Kari Kamiya, narrating her relationship with Tai.