The Older Sister-in-Law of a Child-Rearing Heroine

Title auto-translated

Also known as The Heroine's Sister-in-Law in a Childcare Story · 육아물 여주인공의 새언니

by Tae Jiwon, Beomlam · Updates every Thursday

Updated Jun 24, 2026

Synopsis

She's been reincarnated as a villainous side character in a child-rearing fantasy story — a worthless imperial princess who obsesses over the female lead's older brother, ultimately poisons the heroine, and comes to a miserable end. No thank you. She resolves to want nothing to do with any of them and prepares to make her exit. Then she accidentally saves the heroine, and everything goes sideways. Suddenly the heroine's terrifying older brother is vowing to hunt down anyone who harms his sister to the ends of the earth. The useless imperial family means nothing to him. And he's cheerfully wondering aloud why people call him a mad dog if a mad dog is apparently capable of choosing its targets. Easy there. She just wants to retire to a seaside villa and enjoy her life, her dreams, and her money — but then he's gripping her hand like he'll never let go, confessing that losing her felt like an endless nightmare. To make matters worse, the adorable heroine is pressing the keys to the family vault into her hands, and the heroine's younger brother — who always looked at her like she was a nuisance — is starting to act very strange too. What is happening to everyone?