its very conplicated but basically humanity gets killed by asteroids and humans bones turn into gemstone people, souls turn into lunarian people who live on the moon, and flesh turns into jellyfish people who live in the water. the story is about a gemstone person called phosphophyllite, and theyre fragile. when a gem person shatters, they can be reassembled, but if they lose a body part they lose the memories inside the bodypart. like if they lose 1/3 of their bodies, they lose 1/3 of their-
memories. so phosphophyllite (phos) basically wants to find out more about the world, but they keep shattering and losing pieces of themself. they find other old genstone's body parts to replace phos' body parts, and it changes phos' personality each time because the memories in the new body parts were someone elses. its a very philosophical and emotional manga that has lots of buddhist themes. if you want something to think about for the rest of your life read it.