Yatsuzaki Loop Reijou Wa Ruikei Jinsei Hyaku Nenme Ni, Hajimete No Koi Wo Shita.

"God, how many more times will I have to repeat this life?"
On the day before her wedding, Lydia, the daughter of a baron, is torn to pieces by a demon and returns to life. Her 100th birthday has arrived.To escape her playboy fiancé, her father who treats her as a tool in a political marriage, and the demon itself, she tries various methods to avoid the cycle—including "staying hidden in the royal castle" and "becoming a holy knight"—but her fate remains unchanged, and Lydia finally breaks down after her fifth life. Just as she's about to spend her final moments in the garden of her memories, a young man appears bearing a bouquet of flowers...!?

A love fantasy about a misfortune-filled young lady whose life is turned upside down by a demon!