Missed My Happy Ending, Met the Demon Grand Duke

Read Manhwa / MangaToon Missed My Happy Ending, Met the Demon Grand Duke / I Slept Through the Happy Ending Flag, and a Demon Grand Duke Showed Up / ハピエンフラグを寝過ごしたら、悪魔大公が出てきました

One day, college student Charlotte finds herself reincarnated as the heroine of a manga, the marquis’s daughter Charlotte. In the original story, when the heroine goes to pray at the cathedral, she meets an angel who grants her wish. Charlotte, who secretly loves Prince Isaac but can’t be honest about her feelings, receives the angel’s magic so that her true heart will reach him, gradually grows closer to him, and in the end they end up together.
After reincarnating, however, this Charlotte accidentally oversleeps the very time the angel is supposed to appear, and instead has her wish overheard by a demon. Annoyed at being mistaken for an angel, the demon Maynard twists her wish and makes it so that she can hear Prince Isaac’s inner voice. Worse, this Isaac is nothing like the original—he’s a black‑hearted, cruel yandere. Horrified by his true nature, Charlotte starts avoiding him, but that only piques his interest and puts her in even greater danger.
The one who comes to her rescue is Maynard, the demon living incognito as a grand duke of the same kingdom—but dealing with him is anything but straightforward…