Me, a Saint? Nay, I am a Villainess! ~Therefore, I shall have the honor of preventing this TPK~ is a Manga/Manhwa/Manhua in english language, Shoujo series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.cc fastest updating comic site. The Summary is

After waking up from a nightmare, Iris realized she was the Villainess in an otome Game. But in the game, all of the love interests had a hidden abnormal way of loving, so no matter which one you went after, you'd have a Happy Bad Ending. And in the worst case scenario, the royal castle goes up in flames...and if you didn't capture the heart of any love interest, the Villainess Iris would stab the Heroine..?! But she refuses the idea of such a future, therefore she'll take it upon herself to prevent her ruin and Happy Bad Ending!