Your lover has a serious effect on you, literally. When you two get together, you focus on serious matters. You're thorough in your thought processes together; if you have an issue to talk out, you do so with serious intentions to get past the obstacle and never let it happen again.
This makes for a lot of pressure for a romance, but it's ideal for the long-term relationship, because it helps to ensure that you two always communicate well and carefully, and that you're considerate of each other whenever problems arise. You don't just help each other with problems in your relationship, either; your partner also helps you deal with outside issues in your own life, offering advice on anything from your career to your friendships to your relationships with your family. Other more difficult aspects to your relationship are aided by this generally positive one, because of the good communication it fosters. Any issues that arise find real solutions; any ideas either of you has are either grounded in a stable reality, or discarded quickly as unusable. You work well together; this aspect would support a business or creative relationship as well as a romantic one. Practical experience, knowledge and advice should be a focus between you, and you should both try hard to put your best effort forward in this relationship.