I love the idea that the twins are equal, but that it's an equality of balance rather than equality that comes from their relationship being static. If that makes any sense. Sometimes one is in charge, sometimes the other, and both are OK with it. And that's what makes it possible for them to allow another person, esp. one who understands that balance, in.

*points at Ginny's expression*

Uh-huh. That's how she's gonna look when she realizes what these three are getting up to in the back room of WWW most nights. :D