Otome Game no Hametsu Flag shika Nai Akuyaku Reijou ni Tensei Shiteshimatta... (Link)

Published as a light novel series starting in August 2015. Adapted into a manga starting in August 2017 and an anime series starting in April 2020. Inspired a variety of spinoffs, as well.

Katarina Claes is a bratty noble girl. When she is eight years old, she trips, falls, hits her head–and awakens memories of her past life.

In her previous life, Katarina was an ordinary Japanese high-school student. Moreover, she was the opposite of a noble lady: in elementary school she ran around the fields, climbing trees like a monkey, and in middle school she became an otaku, reading romance novels and manga, watching anime, and playing otome games.

In her first year of high school, on the way to school one morning, she was killed in a traffic accident. And the world she was reborn in was the world of the otome game she was playing at the time: Fortune Lover. Unfortunately, Katarina Claes was a villainous girl who was the protagonist's rival and tormentor, and a terrible fate awaits her. Katarina resolves to use her knowledge of the game to avoid her coming doom.

However, Katarina is extremely dense, and fails to recognize that more than her active efforts, the change in her personality due to her awakened memories is having a great effect on everyone around her.

Finally, when she is fifteen years old, she enters the school of magic, where the story of the game begins. What fate awaits Katarina?