I'm honestly not sure why, but should you decide on Rarity and I decide on Lapis, I'd like them to know each other. I'm not sure they'd "get" each other, because Roberta/Lapis is pretty anti-social and unhappy, and perhaps not Rarity's idea of stylish? (Idk, though, I'm canonblind to MLP of any kind.) But I'd like to see where things end up.