One day, Rain went mushroom picking alone in the forest. Unfortunately, he slipped, fell off a cliff, and died. Mycelium slowly grew over his corpse.

Ten days later, after the search was called off, he suddenly came home as if nothing had happened. He hugged his crying parents with the same innocent face as before.

When his body is damaged, he uses hyphae to absorb organic matter and regenerate his body.

He's a shy boy, so he admires Rose's bravery and often follows her around.

Rain's flesh is made of mycelia and mushrooms.