is a Japanese light novel series written by Kotoko and illustrated by Ataka. Originally published as a web novel on Shōsetsuka ni Narō since April 2022, it later began publication by Enterbrain under its B's Log Bunko imprint in November 2022. A manga adaptation illustrated by Minori Amanatsu and Ayumi Nakashima began serialization online on Kadokawa's KadoComi website under the Flos Comic brand in December 2022.
Plot A Japanese office worker is reincarnated as her favorite romance novel's villainess Grace Saintsbury, who plans to prevent a war by breaking her relationship with main character Duke Zane Winslet in order to get him together with the novel's heroine Charlotte. Much to Grace's chagrin, Zane remains obsessed with her afterwards, with her former ally Count Gardner taking an interest.
Media Light novel Written by Kotoko, Breaking Up Was the Plan, the Duke Falling For the Villainess Was Not! originally started as a web novel on Shōsetsuka ni Narō, with its first two chapters published on 3 April 2022. A light novel version, illustrated by Ataka, had its first volume published by Enterbrain under its B's Log Bunko imprint on 15 November 2022. In October 2025, Cross Infinite World announced that it has licensed the light novel for English publication.
Manga A manga adaptation illustrated by Minori Amanatsu and Ayumi Nakajima began serialization online on Kadokawa's KadoComi website under the Flos Comic brand on 31 December 2022. The first compiled volume was released on 2 May 2023.
Reception Rebecca Silverman and Lauren Orsini of Anime News Network gave the first volume a 4 and 3.5 (respectively) out of 5. Silverman praised the unique approach to the villainess genre, drawing comparisons of the "face-to-face with your book boyfriend" romance concept with self-insertion fanfiction, while Orsini called it "a compelling, complicated take on the villainess story that reckons with what it really means to be a good person". Sean Gaffney of A Case Suitable for Treatment felt that the first volume was lacking in darker moments despite their presence, remarking: "It’s still MOSTLY a comedy, but the pull from darkness is what makes it interesting ... I hope [the next volume] keeps the dark stuff as well.".
Orsini praised the first volume's handling of the personality change associated with isekai reincarnation, while Gaffney showed awe over Grace's nature as a villainess. Regarding the first volume's structure, Silverman called the translation "smooth and very readable ... with a light but not fluffy vocabulary", and Gaffney called the addition of a prologue to the first volume "rather pointless".
See also The Final-Boss Prince Is Somehow Obsessed with the Chubby Villainess: Reincarnated Me, a manga series with the same writer Grinding My Way to a Happy Ending: If Only My OP Big Bro Didn't Make Things So (Sister) Complex!, another light novel series with the same writer In Another World, My Sister Stole My Name, a manga series with the same writer
References
External links at Shōsetsuka ni Narō at KadoComi