Inverted: Alice and Bob are an Official Couple. Many fans refuse to recognize them as such.
Subverted: Alice has a crush on Bob, but it's one-sided.
Double Subverted: But it turns out Bob just Cannot Spit It Out until he finds out about Alice's feelings. Then they get together.
Parodied: Alice and Bob are inanimate objects, and they're not even logically connected inanimate objects (i.e. not a case of "And the dish ran away with the spoon", but more like "And the dish ran away with the radio".)
Zig Zagged: Sometimes Alice and Bob are head-over-heels for each other, sometimes they are nothing more than Platonic Life Partners, sometimes they are treated as casual acquaintances (as they are in Canon), sometimes they don't appear together at all, sometimes they can't stand one another.
Discussed: "Alicia, are you sure that Robert is the one for you? After all, you're a 16-year old human girl and he's a Martian vampire. I understand that "true love conquers all", as the saying goes, but maybe you still want to consider going out with a normal guy?"
Conversed: "Whoa, never saw that pairing coming".
Deconstructed: Alice and Bob may not even know each other, or even like each other. Just being in the same room or the same series/movie is not enough for a healthy relationship.
Reconstructed: But, somehow, it works. Alice and Bob learn that they have a lot in common, and that they really do like each other. Before long, they too are exclusive.