" There are worlds built on rainbows and worlds built on rain. There are worlds of pure mathematics, where every number chimes like crystal as it rolls into reality. There are worlds of light and worlds of darkness, worlds of rhyme and worlds of reason, and worlds where the only thing that matters is the goodness in a hero's heart. "

― Seanan McGuire , Down Among the Sticks and Bones (Wayward Children, #2)