I started reading C.S. Lewis in elementary school, checking out one Narnia book at a time from the library and loitering among the shelves longer than my teacher's pass allowed. The amazing thing about him as an author is that, as a child, I loved the fantasy he'd conjured, and now, as an adult, I'm going back and reading through his non-fiction, and realizing that he was never an author of children's books, but such a bright thinker and creative mind who should be endlessly quoted. His writing is relevant on every level; his stories were never for children, but for everyone.
In The Problem of Pain, Lewis talks about lions - actual lions - and brings up the problem with that old "lion laid down with the lamb," parable. To very loosely paraphrase him, he says that to take away the lion's wish to kill the lamb would be to change what the lion is, and how can we value such a beast once we've stripped it of its lion-ness?
"I think the lion, when he has ceased to be dangerous, will still be awful: indeed, that we shall then first see that of which the present fangs and claws are a clumsy, and satanically perverted, imitation. There will still be something like the shaking of a golden man: and often the Duke will say, 'Let him roar again.'"
And this is where I take Lewis's words and most likely butcher them by applying his ideas to my own work. He's talking about animals...but also not. Because humans are animals as well.
I don't like when I'm reading a book in which humans are referenced as animals in a purely sexual sense. We're more complex than that; let's make the animal metaphors more subtle. I can't stand the predator/prey comparison in male/female relationships. Lions don't mate with lambs; they run them down, kill them, and eat them - literally eat them. The lion's mate - if she is to be a true mate - has to be a predator too. She can't be his food source. She has to be his partner. They can be different, their natures can compliment rather than compete. Wild lions, tame lions, zoo lions, deranged loner lions, strong lions, weak lions, maneater lions, leader lions and tyrannical lions - they all have claws. Male and female; black, white, brown - they can all roar.
I'm coming to the point - promise.
When it comes to character development, to creating mated pairs, I always take the lion into consideration. No one is ever one-dimensional. No one is ever "just the quiet one." It's not a case of the man being strong and taking care of the weak woman. Or the strong woman telling the weak man what to do. Please. Make me barf. They are both strong - they are both lions - even if their claws come out at different times, even if that strength shows itself in different ways.
Whatever kinds of relationships you're writing, whatever gender, race, sexuality, or creed, no one in these scenarios is ever the lamb. Respect your characters, and the readers will respect them. We're all lions. And even tame lions have fangs.