revenge of others kdrama

Kimber Klein, a janitor, goes to pick up her child as usual, but she's humiliated by her former classmate, Lara Spencer. On her way home, a convoy of luxury cars passes by, and she learns that her father, who abandoned her and her mother, is now the richest man in the country. Kimber doesn't believe it. Her father, Ronan Klein, hands her a black card and leaves. Kimber takes her child to a high-end restaurant, only to be humiliated again by Lara. When she tries to use the black card, it gets declined, and Lara mocks her and demands she lick her shoes. For her child's sake, Kimber complies. Just then, Ronan's men arrive and turn the situation around. Kimber finally realizes she is truly the daughter of a billionaire, kicking off her journey of revenge and reclaiming her rightful place.