I Was Reborn as a Villainous Young Lady Who Awakens as the Demon King, So I Tried to Become the Strongest Evil, But For Some Reason I'm Being Called a Holy Woman

Reincarnated as a villainous young lady destined to become the Demon King, Cynthia swears to become the greatest evil for the sake of her beloved Sophia. In her attempt to do so, Cynthia repeatedly commits wicked deeds, but for some reason they turn out for the good, and she comes to be revered as a saint. Furthermore, she is also adored by Sophia, the heroine who was supposed to become her enemy in the end... (The protagonist does not suffer terrible fates. The R15 rating is just a precaution.)