is a Japanese light novel series written by Mary Doe and illustrated by Kuga Huna. It began serialization as a web novel published on Shōsetsuka ni Narō in June 2022. It was later acquired by Square Enix who began publishing it under their SQEX Novel imprint in March 2023. A manga adaptation illustrated by Suzuka Stellagi began serialization on Square Enix's Manga Up! manga service in October 2023.
Synopsis Wellmy Ernest, a daughter of a commoner becomes a member of an Earl's family as her mother marries the Earl. She becomes sisters with the Earl's daughter Iora, and makes her life a nightmare, taking her love interest and her position as heir to her family. She later attempts to marry Iora off to Aides Ormirage, a Lord of Magic who is said to be cruel, and it leads to her and her parents getting tried for their abuse of Iora, just as Wellmy had planned.
Media Light novel Written by Mary Doe, Proud to Be the Villainess began serialization as a web novel published on Shōsetsuka ni Narō on June 4, 2022. It was later acquired by Square Enix who began publishing it with illustrations by Kuga Huna under their SQEX Novel light novel imprint on March 7, 2023. Seven volumes have been released as of April 7, 2026.
In February 2026, J-Novel Club announced that they had licensed the series for English publication.
Manga A manga adaptation illustrated by Suzuka Stellagi, titled Proud to Be the Villainess: I'm Doomed After Stealing my Half-Sister's Fiancé and Having Her Banished, began serialization on Square Enix's Manga Up! manga service on October 15, 2023. Stellagi would serialize the manga until its 16th chapter, afterwards she was replaced by Yume handling composition and Medamayaki handling illustrations from chapter 17 and onwards. The manga's chapters have been compiled into four volumes as of June 2026.
The manga's chapters are published in English on Square Enix's Manga Up! Global app.
Reception The manga adaptation was ranked 8th in the sixth Sanyodo Bookstore Comic Awards in 2025.
References
External links at Shōsetsuka ni Narō