[Everyone's Darling + Truly Adorable Child + Evil Villain System (Idiot Edition) + Everyday Child-Rearing]
On the very day four-and-a-half-year-old Mumu is adopted by Wen Shixu, the richest man in the capital, she is mistakenly bound to an Evil Villain System.
[Today is your twenty-eighth birthday. Now, everyone has turned against you. You killed your alcoholic, abusive husband and fled your home. You refuse to accept this. You want revenge!]
Mission One: Dress up as a ghost and scare your grandmother, who has heart disease, to death.
Mumu hides behind the curtains, ready to jump out and scare her in the middle of the night, but discovers a witchcraft doll hidden there.
Grandma: Our Mumu really is the best child!
Mission Two: Poison your mother's medicine.
Mumu doesn't know what poison is, so she has a brilliant idea and adds two big spoonfuls of sugar.
Mom: Our Mumu really is the most devoted child!
Mission Three: Tear up the contract Dad is about to sign.
Mumu tears up the contract, inadvertently saving the Wen Group from falling into a rival's trap and sparing it a huge loss.
Dad: My precious daughter is so thoughtful!
Mission Four: Smash your brother's favorite collectible figure.
Mumu grabs the figure and smashes it open, discovering a poison sachet hidden inside and saving her brother's life.
Brother: Mumu really is my lucky star. I'll give her the very best!
Under the villain System's direction, Mumu commits more and more misdeeds, yet becomes even more adored by powerful people from every walk of life.
Watching Mumu dote on everyone while they dote on her, the System finally breaks down.
Wasn't she supposed to grow up into an evil villain hated by everyone?
How did she become everyone's darling by doing bad things?!
When the real heroine returns, vowing to use the Wen family as a stepping stone, she too realizes something is wrong.
She's the heroine, so why does everyone like that cannon-fodder girl instead?