You Aren't My Favorite, Your Highness...! As an Evil Princess, I've Entered a Romance Plot Where He's Fallen Head over Heels for Me?!

Aline was betrothed to the crown prince Clovis when they were children, but they have never been close. One day, she suddenly regains memories of her past life as an ordinary office worker when she passes by the game's heroine! Originally, she was meant to be the villainess, but the heroine was always her favorite character, and now, she's determined to support her happiness instead. Aline plans to break off her engagement with Clovis, but it backfires, only making him more intrigued by her. His sweet words begin to make her falter, but will she listen to her heart?! An unpredictable love story of the former villainess, her beloved heroine, and the prince caught between them.

(Source: MangaPlaza)