I’m in a Secret Relationship with the Emperor and I Don’t Know About It

A woman is reincarnated into a romance fantasy novel where the tyrant emperor is destined to fall in love with the saintly heroine. As a minor palace employee with no role in the main story, she only cares about surviving work and living peacefully.
Things change when she starts dating an incredibly handsome man she assumes is just another ordinary extra. Their relationship slowly becomes more serious, but she later discovers he is actually the emperor himself. Now, while the empire buzzes over the emperor’s rumored romance with the heroine, she’s secretly involved with him without even realizing who he truly is.