If someone is propositioning you, it means that they are offering you sex. It is a more polite and euphemistic way of saying someone wants to bang you.
In the case where the prepositional phrase “in bed” is added to the end of a fortune cookie saying, the entire phrase will always makes sense and could potentially make you more appealing to your date.
In an attempt to captivate and entice Jill, Matt applied the Prepositional-Proposition Theorem to his fortune cookie saying and announced “Your talents will be recognized and you will be rewarded...in bed.” Unfortunately, his date Jill was not impressed.
While our lifespan is the number of years we will live, our healthspan is the number of healthy years we will have and our sexspan is is the number of years we will continue to be healthy enough to continue having an active sex life.
A lighthearted reaction upon receiving disappointing news of some sort. Usually something that isn't a particularly a big deal, esp. when it primarily affects someone else - sort of a mild schadenfreude. Sometimes doubled or tripled, and possibly said in a sing-songy voice for added comedic effect to imitate a muted trumpet, which is how the meme originated.