The Youngest Child of the Family Is Preventing the World From Ending

"The stupid youngest one, the one who doesn't know how to do anything, but causes trouble with her cute face." Exasperated, I looked in the mirror once again and exclaimed. "Why am I the 'stupid youngest one' Diana Cartier!" In the novel 「The Ending Can’t Be the Destruction of the World」, Diana is an evil woman who repeatedly commits evil deeds and is brainwashed by the villain, contributing greatly to the destruction of the world! If something could go wrong for the villainess, it will. But when something went wrong for me, I recalled my past life instead? As an ordinary college student in my past life, I made up my mind when I realized that I had been reincarnated as Diana Cartier, the villainess in the novel. "The world is going to end." "But I'm not going to let it happen." Yes, I will prevent the end of the world with my own hands! And save my brothers from the conspiracy at the same time! Wait a minute. What's that pitch black thing on the floor over there? Wait. That face, where have I seen it before? 'Is it Linus del Stein!?' Why are you lying there, Mr. Protagonist of the novel that will destroy this world? Diana and her brothers are trying their best to stop the end of the world! And cute animals and other stuff? Our sweet youngest is preventing the end of the world, get out of the way!