Princess-knight Lilia / Himekishi Lilia

The main character Princess Lily is the heiress to the royal throne. However, this does not suit her brother Prince Dirk, and he begins to weave intrigues by making a contract with the dark forces of demons. Dirk learned that if he awakens Lily's hidden power, he will be able to get the most powerful army that the light has never seen. However, to awaken the power, Princess Lily must achieve incredible ecstasy through sexual pleasures. Well, Dirk will have to experiment to find the key to Lily's secret secrets.