Thats unfortunately not the case here
You should read "my cute beast" then.
The MC's bf is from a big family and he has a fiancé (that the MC didn't even heard about). Since their wedding is not too far, the fiancé (that learned that he had a gf) went to the MC and told her she was her bf's fiancé and even tho she doesn't love him, she want to build a good relationship with him for the sake of their families
ANNNNNNND the MC said ok ( she was already having some issues with the bf) and the two girls became friends and super close to each other.
The MC is a real badass girl, doesn't get jealous over other girls and have confidence in herself. You would love it
imagine if the author made the readers think that the pink haired was jealous and mean but in reality she ends up being best friends with our girl. that would be an amazing twist, i don’t want to read about girls hating each other tbh.