The Fierce King and the Substitute Princess

Overview

The kiss includes the intertwining of tongues." A false princess is taught by a cruel and ruthless king to perform a nocturnal... "I can't hold back my desire to embrace you." Tiana, a novice nun, is chosen to marry King August of the neighboring kingdom in place of the princess. On the night before her audience, she nearly stumbles, only to be saved by a handsome knight who turns out to be the king himself! In a whirlwind of surprise, they spend their first night together. "Don't worry. I'll teach you everything," he whispers, his gentle fingers softly awakening parts of Tiana that no one has ever touched. Her body melts with newfound warmth, and her feelings for him deepen with each passing moment. Even though she's a fake princess, is it really okay to fall in love with King August like this...? (Source: BisouBisou Comics)

Source: AniList