The Twelve Kingdoms Wiki

Ranka (卵果, eggfruit) are the enchanted fruit that all life is hatched from. Translated as eggfruit. Ranka grow from special trees; depending on what sort of life will hatch from the ranka, they may grow on riboku, yaboku, or the shashinboku. The fruit are golden in colour and round like eggs. They cannot be picked from the tree they have grown from until it is time for the ranka to hatch.

Humans, livestock, and crops grow upon the tree when people pray to Tentei, who will allow ranka to grow in response to these prayers. Humans may only pick ranka of human beings that they have prayed for.

Ranka, if blown from their trees before hatching by shoku into Hourai, will be implanted into the wombs of human mothers and born as taika.