Higeki no Genkyou to Naru Saikyou Gedou Last Boss Joou wa Tami no Tame ni Tsukushimasu.

Pride Royal Ivy is the final boss and all-around scum in the otome game Our Ray of Light. She committed innumerable crimes—from enslaving her adopted brother in a soul-binding contract to abusing her position against the servants in the household. In short, she is a villain of pure evil. A normal high school student in Japan reincarnates into the eight-year-old body of Princess Pride. The first order of business: survive to see another day. Using her cheat-like abilities, she resolves to save her father, rescue the kingdom, and become a kind and benevolent ruler. And so, Pride resolves to change her fate, no matter what it takes! [Written by MAL Rewrite]