Although Toyotamabime, the daughter of the sea god, became pregnant at Ryugu (the palace of the dragon king believed to exist at the bottom of the ocean), she went up on the land as she thought it was inappropriate to give birth to a child of Tenjin (the heavenly god) in the sea.
トヨタマビメは龍宮で懐妊したが、天神の子を海の中で生むわけにはいかないとして、陸に上がってきた。