Koori no Reijou wa Osananajimi Koutaishi ni Dekiai sareru: Hatsujou no Uzuki wo Amaku Mitashite

The Grace family has possessed healing powers for generations. Yet, those powers come with a certain price: those whose power manifests must serve as an aide to the royal family. Stella has been eagerly awaiting the day her own power manifests. One day, while she is having tea, Lucas—her childhood friend and the crown prince of the Kingdom of Lydia—appears. He is actually Stella's first love, but ever since a certain incident, their relationship has remained awkward and strained. Suddenly Stella feels something strange come over her body and hurriedly leaves the room, yet her body only grows hotter and hotter. As her consciousness is thrown into disarray by the aching of her body, Lucas, worried about her condition, discovers her secret and asks, "Is the price of your power... lust?" A devoted, obsessive prince and a young lady with a fear of men (and an aroused constitution). This is a sweet love story between two childhood friends who can only be honest with each other in bed.

(Source: Bunkasha, translated)