" Probably lots of people have died in the castle,' Susannah was saying sleepily. 'Cats, too. Lots of cats. The whole courtyard is probably full of graves, and we walk over them all the time.'

'I think,' Layla said, quite seriously, 'that people and cats turn back to the earth after a while. So what you walk over is just earth, Susannah. "

― Eloisa James , Once Upon a Tower (Fairy Tales, #5)