"Another world! There's an entire species of them that, uh," Connie looks worried for a second, "that aren't nearly as nice. Most of the Gems on my world--uncorrupted ones, anyways--are remnants of an old rebellion that protected Earth from being destroyed. That's why I need to get back. Since the Diamonds finally have Earth back on their radar, the Crystal Gems could be in the middle of another war right now and I'm not there to help!