Someone living on the top floor of a panda house, or a tree. More specifically, a ponderosa tree. These people can be described as tree-hugging liberal badasses who care about the good will and fortune of pandas.
TK lives at the top of ponderosa. She's kind of liberal, but she's a happy panda.
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.