According to Greek mythology, the constellation 'Cassiopeia' was created when Poseidon tied the Queen of Aethiopia to a chair and placed her in the sky, punishing her for proclaiming that she was prettier than the Nereids.

Ask anypony in Equestria, however, and they'll tell you that story is a bunch of baloney.

This is the story of Cassie, a young filly fighting for her life, and how she found a friend and kindred spirit in the Princess of the Night, forming a bond that would alter the night sky forever.

Thanks to ocalhoun for proofreading this story!