Marluxia 'hmm'ed quietly. "I have a feeling that the definition of a soul is different for you and I. Souls merely animate the body from what I know. Its presence determines life and death." It could be easy to confuse the two, he supposed, judging from tales from other worlds he had heard before. "As to that question of yours, that isn't how Nobodies lose their heart. Often they are stolen by the Heartless, creatures formed of the darkness born within the heart. They steal in order to increase their number and live only on instinct. There are a few around here and in the worlds in the other floors. You'll recognize them by their yellow eyes."