Mui (夢衣)

When I thought I was sick and ended my life without going to school, I reincarnated as the villainess Sylvia in the world of the game I played! I was trying to enjoy my second life with a strong body that can move freely. Due to Sylvia's older brother Rafis, she fails to avoid the ruin flag and both are banished to the "Forest of Death". Rafis begins to say that he will destroy his country for Sylvia in a severe sister complex..?! source: MangaUpdates

“I” have been reincarnated as Felicie, the villainous heroine of a notoriously terrible game—and the future awaiting me is a deadly one: the moment anyone’s affection level drops to zero, I’ll be killed! Faced with three ruthless brothers from a powerful ducal family, Felicie is nearly driven to despair. But armed with memories of her previous life, she begins doing everything she can to break each of her death flags and rewrite her doomed fate. Can she survive this deadly game and turn everything around…!? A desperate young lady’s life-or-death survival strategy and ultimate comeback begins now—!!