The start of a grand scheme

Claire, princess of an extremely wealthy kingdom, has an unrequited love for her best friend Sofia, daughter of the duke. Upon Sofia getting betrothed to another Claire fears she'll lose her and tries to make her realize how she feels and to get her to return those feelings.
Sooo, sapphic royalcore with a childhood best friends trope
Enjoy!! ^^
(PS: js to be nicer the fiance is aro/ace)