How is This Hot Duke Just a Background Character?!

*I was reincarnated as a mob character from an otome game, and my fiancé is a handsome duke.* I've been transmigrated as "Leticia," a mob character from an otome game. I was forced to take Lionel as my fiancé by my twin sister (who, by the way, has the worst personality). The first time I met Lionel, he was nothing but chubby and fat, just as the rumours said he'd be… However, me being me, I realised that Lionel is an unpolished gem with potential to shine, so I decided to re-invent him. Even if I'm a mob character, my days of doting on my fiancé began when my fiancé transformed both inside and out. --- *I was reborn... as a background character in a romance game?! And my fiancé is a hot duke?!* Reincarnated as 'Leticia,' a background character in a game, I found out that my twin sister, who has a horrible personality, pawned her fiancé, Lionel, off on me. When I first met Lionel, he was just as chubby as I'd heard... But I soon realized he was a diamond in the rough and decided to make him shine! But that's when I discovered that my newly hot fiancé is acting like he's head over heels for me...!