The silkworm is inserted into a loose hole and it begins to spin cocoons around the perimeter of the hole and creates a new layer of hymen.
It was the old way of restoring a broken hymen so that a slut could re-enter the marriage market and still claim to be a virgin. This method is called 天蠶變。
When the man sees blood after breaking the cocoons, it's actually the blood of the dead silkworm. This method got 口訣, I not anyhow 編故事 one, OK?
天蠶再變貞操煉
淫娃蛻變處女現
熊熊慾火老婦艷
新柔兩地到處騙