Math ap Mathonwy

In Celtic mythology, Math ap Mathonwy was a king who needed to rest his feet in the lap of a virgin unless he was at war, or wanted to be. When one of his virgins, Goewin, was raped by Gilfaethwy, she was replaced with Gilfaethwy's sister, Arianrhod. She immediately gave birth to a young boy (Dylan) and a blob.