This manhwa is similar to The Obsessive Male Leads Wants to Eat Me, but has a different storyline.
The female character (FC) died in her real world, where she likes to read Boy's Love (BL) novels/manhwa, and reincarnated into her favourite story, becoming a blonde-haired villainess girl who bedevils the male lead (MC), who has dark-hair and red eyes. Her red-haired mother in the isekai world is the one who captures the MC and tortures him.
The FC is often ill, so she must be taken care of by the doctor, who has long white/blond-hair and wears circle-shape glasses. The MC's partner should be the blond/white-haired boy, who is the little brother of the FC's doctor. Since the FC realizes that her evil act may lead to her death (according to the real story), she then started to treat the MC nicely and is still going to be the cupid between the MC and his real partner (the doctor's brother).