Housekeeper Manhwa

I think it’s Korean? About a poor woman hired by a sick children’s book writer to destroy her family. She becomes a housekeeper for the family and seduces all of them(a son, daughter, and the father). It ends with her shooting one of them and burning the house down I think.

Other random details are that she also seduces the gardener and he ends up getting hurt somehow. Before she worked for this family, she worked at a factory and lived in workers dorms or an apartment with her coworker. The coworker’s boyfriend is interested in the female lead, and tries to flirt with her. The coworker is pissed and kicks the female lead out(instead of breaking up with her cheater bf like wtf??). I know that she wears a simple black dress as like a uniform for the housekeeper job. It’s set in modern day, not fantasy or historical.

I know there’s like so many maid stories out there but please help me out guys I’ve been searching for so long