Kiraware Oujo wa Juuou-sama Okiniiri: Doku-hime ga Reset shita Jinsei de Dekiai saremasu

Overview

First Princess of the Elixir Kingdom, Roselia is referred to as the 'Poison Princess' and is hated by many. She was unfortunately born with the power to create poisons rather than the ability to create 'Cure Potions'--a healing power passed down in the royal family. Roselia was given the chance to have her position solidified as the heir to the throne after her mother died. That was the condition? To be able to create Cure Potions before the age of 18. Roselia, alone, tries her hardest to create Cure Potions, and then she meets the one of the few people who have ever treated her nicely, Lord Elliott, her cousin! She finds herself drawn to him and he proposes!"Do you wish to rewind your life?" At her lowest moment, overcome with despair, the Poison Princess's fate changes, and she heads off onto a new journey to find happiness and... maybe even love...?

Source: AniList