Inverted: Both Alice and Bob think the other is interested, but neither of them actually are.
Subverted: Alice and Bob spend a lot of time together, always seem perkier while the other is around, and even get flushed around each other often, but neither has any romantic interest in the other.
Double Subverted: ...until a situation Gone Horribly Wrong leads them to think they're going to die, and they discover an interest in one another, only for them to be rescued just before it all comes out.
Parodied: Alice and Bob quite obviously like each other, but when asked about their relationship, they act a though they are repulsed by the thought.
Zig Zagged: Bob wants to admit his feeling Alice, but she's involved with Andy. At the same time Alice develops green eyes due to Bob developing a closer relationship with Carol. Eventually both Bob and Alice return to being single but are still unable to admit their feelings for each other.
Alice and Bob meet, get to know each other, eventually fall in love and develop a relationship.
Alice and Bob meet, and are genuinely not attracted to each other.