Gift of the Fox
In the kingdom of Wanglong, slave girls work in the royal palace. Three girls - Tamie Beanson, Tiegan Brown and Liz Schettner - are close friends to each other. They serve as water-maids in the palace and occasionally do some other work.
The three girls get to contemplate the life of seven princes - the sons of Wang Ru - the emperor of Wanglong.
Tamie has a crush on one of the princes, and wishes to get closer to him - Wang Shao, the most mysterious of the seven. But as she is only a servant, she gets no chance to get closer to the boys. Furthermore, she is a woman, and women servants are regarded as even lower than men. The men servants sometimes get to become the princes' personal servants, aiding them in hunts and battles.
One day, Tamie rescues an injured fox from being captured by the princes, and her friends help her get the fox back to her feet.
Tamie, grieved that she is unable to reach her sweetheart, goes alone in the forest to lament, and dreams only if she were a boy. Once she makes this wish, her friend fox from before appears and breathes at her while she's still sleeping.
Later when Tamie wakes up, she feels she has somehow changed... but everything gets clear when she crawls up to the river and looks into the water, just to discover what that 'change' actually is...
She looks in the water, but it reflects a boy...
The Kindle version of the book is available for $0.99 on the link: https://www.amazon.com/dp/B07DYCPXRC
The paperback version for $8.70 can be found on the link: https://www.amazon.com/dp/1983246131