Light manga isekai

After dying from illness, I woke up not as the popular novel's heroine, but as her selfish, chubby, villainous older sister, Celine! Determined to avoid the miserable fate of being killed by the hero prince as written in the novel, I vow to reform myself with all my might and start struggling. But before I know it, I'm entangled in unexpected doting and obsession! Can Celine truly grasp 'peaceful happiness' amidst being excessively loved by a yandere in this fantasy love story of reincarnation into another world?

[A villainess who changes fate in exchange for love!] The daughter of the Marquis, Milliana, was engaged to the prince and living happily when she was suddenly accused of assassinating the emperor and executed. However, at the moment of death, a voice heard from somewhere led Milliana to experience 1000 lives. In each life, she acquires various abilities, and in her 1001st life, she finally returns to her own life as 'Miliana'. Events that did not happen in her first life, people she never met, and even plots lurking here and there... Milliana tries to do everything she can to save the people she lost in her past life. However, in order to create a 'world where no one dies', Milliana cannot be connected to anyone...?!