I'm going to refuse being a doormat heroine, so I decided to kick out the root cause.

Mother passed away. Not long after that―――― Father brought an unfamiliar mother and child to the mansion. "Nice to meet you! Are you going to be my older sister?" The eyes and hair of the girl looking at me with a smile were exactly the same color as Father's. "Wow, big sister, you have such a pretty brooch! I want one too!" So, my new younger sister? said that moment... Tremendous information flooded through my head. Wait, isn't this that story about a doormat protagonist who gets exploited by her family and a half-sister who takes everything from her? A doormat heroine... the first move in a life of being robbed as the protagonist of a story. So I will... okay, first let me just beat the crap out of this idiot for saying something so stupid. I refuse to be a doormat heroine, so I'll discipline her thoroughly from here on out. While I'm at it, I'll create a rift between the heroine's scumbag father and this half-sister's mother by saying something like, "Did you bring them here as pawns for political maneuvering, and as a bonus, to use the mother for free as a caretaker for your daughter?" That way, this half-sister's mother and this man won't gang up on me nicely. I've broken one doormat flag! Huh? What happened to the hero who picks up and dotes on the doormat heroine? Who cares. The setting is vague anyway. Thank you for bookmarks, ratings, and likes♪ Posted on Alphapolis and Kakuyomu.