The story opens with a forbidden kiss amid a torrential downpour. Outside the Whitmore mansion, the icy‑haughty, domineering Blair Whitmore pins her stepsister Beatrice against a black sports car, obsessively declaring that Beatrice can belong to no one but her. Beatrice’s ex‑boyfriend comes charging in with a gun, and a gunshot rips through the rainy night. Just as Blair yanks aside Beatrice’s shoulder fabric and catches sight of her peculiar mark, time rewinds ten months into the past.
Beatrice moves into the opulent estate when her mother marries into the Whitmore family, coming to live with Blair, her non‑blood‑related stepsister. From their very first meeting, Blair recognizes the iron‑emblem mark on Beatrice’s shoulder yet offers no explanation. Instead, she invades Beatrice’s life with ferocious possessiveness. She barges unannounced into Beatrice’s bedroom, confiscates her phone, meddles in her contact with her ex‑boyfriend, and resorts to locking doors, threats, and forceful kisses to compel Beatrice to stay by her side. Beatrice loathes this dangerous, irrational stepsister‑yet when she is drugged at a bar, it is Blair who rescues her. Covered in blood, Blair carries her home and stays beside the fear‑of‑darkness‑plagued girl through the entire night. For the first time, Beatrice glimpses the protective instinct hidden beneath Blair’s ruthless exterior.
When Beatrice’s ex‑boyfriend resurfaces, Blair’s jealousy spirals out of control. Meanwhile, their father arranges
