On the day I was dumped by my clean-freak girlfriend Mishiro, my father suddenly remarried, turning Yuzuki — a gal who is the spitting image of my ex — into my younger stepsister. My life is changed at once by this little devil who does all the things my ex-gf didn't do for me!
Ore ni Amaete Kuru Yandere Gimai ga Motokano no Imouto Datta is a completed manga by Ibarakino, first published in 2022. It blends romance, comedy, drama and slice of life. You can read all 4 available chapters of Ore ni Amaete Kuru Yandere Gimai ga Motokano no Imouto Datta online for free on MangaPulse; the newest is Chapter 4, added 2025-06-16. The series is finished, so you can read it from start to end in one go.