A Classic Isekai

I wake up in a fancy room. "AHHHHHHHHHHHHHHHHHHHHHHHH!!" Suddenly, I realize I am laying on a bed. Why am I here?? Didn't I die? While I think these thoughts, I am still screaming, so I decide to stop.

I check myself in the mirror, to realize I am a beautiful girl with dark black hair and yellow. Wow, I am so pretty, I think.

A maid comes into the room. "My Lady, are you okay?" She asks, a worried look on her face. I instantly understand my situation with my millions of braincells, so let me have an internal monologue as I stand in place.

I have a really bad but unnamed illness (Which is irrelevant to the plot therefore unnamed), but I really want to keep on living. I read my favorite book about a poor girl who actually is either a saint or has light magic/healing magic inside her. A red flag with stereotypical black hair and red eyes is at the brink of death, and she heals him!! Turns out, he's the Duke of the North?? He instantly falls in love with her and turns from cold to loving.

But, there's always a villainess. The villainess is the duke's fiancé, and hates how improper the female lead is. Oh no, I feel so bad for the female lead!!

Anyway, some stereotypical things happen and then the villainess dies and the male and female lead live happily ever after.

But, is this a error in the system?? Why am I not the villainess??

I mean, I guess it's good for me. I get to live a luxurious life in the castle!! I suppose the timeline right now is right after the duke picks me up, so I just need to act pitiful and get what I want~

"M-my lady?" I forgot about the maid standing there. I look at her with a smile.

"Ah- I'm okay, Mary." My smile charms Mary, because I am the female lead, and she helps dresses me.

While we are walking to eat breakfast, I suddenly encounter the villainess!! It's okay, as long as I don't act arrogant, clingy, or improper, I will be fine...

I bow to the villainess. (I forgot her name, since it was too long and probably in a language that's not English) "Good morning, Duchess. I am Catherine... uhhh... Whitewarth." I made up the last name because I forgot her last name. "Pleasure to meet you." I smile at her pleasantly.

She nods coldly at me. "Good morning, Lady Whitewarth. I am Marleigh Marienana Freian." Ah... I'm not going to remember that... "How are you feeling?"

"I'm doing very well, thanks to you and the Duke's hospitality, Duchess Marleigh," I replied. The name was much easier to say out loud than read in a book. (A.N. I think it's pronounced Mar-LEY???)

The duchess laughs, and I sigh with relief internally. "Of course. I am always happy to extend a hand to anybody who helps me or my husband." She emphasized the word "husband." Without her making it clear, I would have avoided her husband anyway.

I bow again, then take a risk. "Duchess Marleigh... if it's okay, would you join me for breakfast?" She narrowed her eyes.

"Why so?" Shoot. Did I mess up?

"A-Ah, I just think the Duchess is such a respected and proper person. I would like to learn more from you, since... I'm not very familiar with high society." I start babbling. "Oh.. Please tell me if I'm being improper right now." The duchess's face turns into a smile, and I feel relieved.

"I'll accept your offer, Lady Whitewarth." I sigh in relief out loud. Thank god.