Below is a desolate rocky mountain. The angel Nina thought that if she planted heavenly roses there, the hearts of the people living there would become as beautiful as roses, so she went down alone, carrying the flowers. One of the demons whose territory is the rocky mountain looks at her. The young demon approaches Nina to surprise her, but ends up admiring Nina's beautiful hair and extends his hand. However, in Nina's hair was a heavenly rose with thorns that has the power to kill demons. Just as Nina turns around in surprise, the young man is stung by a thorn from the rose and dies. Nina is deeply shocked by the fact that it is her fault that the demon boy died, and when she sees the beautiful face of the demon boy for the first time, The dew of the heavenly rose, which is said to be able to revive any life, comes to mind. Although Nina knows that taking it out is forbidden, she hands it over to the young man. Mark, a young demon who came back to life, tells Nina about his feelings for her. Nina's heart was also drawn to Mark, but the laws of heaven and the devil did not forgive them.

Princess Silvia, a beautiful foreign student from the Cerulean Kingdom, overrules the objections of her five escorts and offers to share a room with Mizuki, who was assigned as a translator and friend by the Japanese police. Silvia wanted to freely enjoy life in Japan with Mizuki, not as a princess, but as an ordinary student. However, there was a rumor about the princess: in the countries she visited, jewel thieves dressed in silver clothes appeared. The Japanese police were not the only ones who suspected a connection between the silver thieves and the princess...