Colette of the Ruined Kingdom -A Bizarre Princess Tale Completed MTL Translation by Ore Teki Shikou - Adult Sex Game

Proof of Maidenhood"
... A mysterious item in the home of queen-in-waiting Colette.
When she loses her virginity, it will disappear.
That item is proof of her intact hymen, and her right to the throne.
To become queen, Colette needs that proof