I had watched this short (but brilliant) animated series a while ago, and just yesterday I re-watched them and fell in love with them all over again. It's just a touching, adorable and well-animated story about a rabbit and a cat that fall in love, in a world in which such relationships are frowned upon. I think it's supposed to be a metaphor for Korean and Japanese interrelationships, but it also works as a metaphor for gay, interracial or inter-religious relationships that are condemned within certain societies. Although it starts off very fluffy and cute, it becomes darker, more emotionally gripping and more dramatic later on. It's amazing how it can tell such a great story without any dialogue at all, just using the animation and music. If you haven't seen this before, you really have to. If you have already, re-watch it!
Embedded below is a playlist of all 5 videos in the series, so you don't have to do anything but hit play and let it roll!