Those poor Slugcats

I melt every time I see a new set of gifs for Rain World or even a picture of a Slugcat. But for all my cooing and fawning, I have to admit I don't really know much about the game. Other than the exploration and puzzle elements we've been able to divine from small snippets of gameplay, I'm not exactly sure what you do in the game. I don't know any of the background story, how the world got to such a state or even what a Slugcat is. After viewing this latest alpha footage, I still don't know these things.

I do know why they call it Rain World though. Make sure to watch to the end.