This aspect lends you an element of competition and extreme behavior that sparks all your interactions; good or bad, it's all up to you. Whether you're on the same team or opposing ones; whether you're playing a game, having an argument, discussing a movie you just saw -- you push each other to say what you really mean, to focus your energies and efforts and get more done than you would have on your own. Hopefully you weren't taken by surprise -- this is a difficult aspect to deal with, especially at first.
You kid with each other, making jokes at each other's expense, riding each other -- and you, especially, could take offense before you realize that you're both just playing around. You two need to remember to convince yourselves to be patient with each other, so you can understand that you're just poking fun at each other. But then there's your partner's opinionated nature to contend with -- they have plenty of opinions and they stand right by them, often at the expense of listening to you or weighing whether they're really correct in their own position. But over time, as you grow to trust and like each other more and more, you allow that helpful influence to start seeping in. You challenge each other on your beliefs, which help you better define them. If you work together as a team, you can find that the slightly challenging energy between you sparks creative action.