This TV anime has announced its premiere in July 2022. Studio Project No.9 (Higehiro) is in charge of the animation, with Shinsuke YANAGI (Bottom-tier Character Tomozaki) as the director and Deko AKAO (Mysterious Girlfriend X) writing the series composition. My Stepmom's Daughter Is My Ex is a Japanese light novel series by Kyosuke KAMISHIRO, with Takayaki's illustrations. Kadokawa Shoten began its serialisation in December 2018, and it currently has 8 volumes in circulation. Rei KUSAKABE's manga adaptation is being serialised by Fujimi Shobo on Niconico Seiga, and as of now, it has 3 volumes available. [Sources: Anime Corner and Crunchyroll]
According to J-Novel Club, which licenses the light novels in English, the plot is as follows:
Ah, high school. Is there any better place to start fresh after a horrible middle school relationship? Nope! Not unless your ex ends up at the same school as you and is now your stepsibling. What was supposed to be a sanctuary of peace where I could avoid ever seeing her again has become a living nightmare! Everywhere I look, I see her – in my house, in my school, in my class. There's no escape! She even claims that she's the older sibling. Like hell she is! But I won't lose to her. After all, I'm the older brother in this new family situation. That's right, we're family now. No matter how much we may have thought we loved each other before, we saw one another's true colors and realized we weren't meant for each other. That's why even though we may keep up a buddy-buddy sibling act for the sake of our parents, things will never go back to the way they used to be.
