I'd love a Tony+Pepper relationship. The kind of relationship where two people are completely comfortable with each other and who the other person is. They see what they get and they're completely cool with that. There are weird aspects in each person that only the other can understand. They know everything there is about each other but they'll find a way to surprise the other anyway. They can be two independent, amazing people on their own but they can't live or survive without the other one.
A Tony and Pepper relationship.