My thoughts are in blue, words to delete are in red, suggested rephrasing is in orange.

To stop a corrupt queen from invading his kingdom, Keil of Istria must find a fearless girl willing to ride the most belligerent dragon in a race that will decide the fate of his homeland. This feels like a lot up front. I don't understand why a race decides things, and why Keil isn't riding the dragon himself Because in the fae realm, clashes are settled by dragon race, and the fiercest dragon is often victorious. However, such a beast cannot be raced by merely anyone. When Keil sets his sights on a Seattle teen aiming for a career as a BMX racer, Why wouldn't he look for a fae to ride a dragon? Why would he search for someone in the human world? he doesn’t expect to have to protect her from life-threatening attacks by wild fae under the queen’s spell. But why not? Wouldn't he expect the queen to do something to defend herself, of play a game? Fae are tricky by nature, and if he is one, why is he surprised? Nor does he expect to fall for her. The stronger his feelings for her grow, the more he questions his mission. Why would his growing feelings make him question his mission?

In a world where humans and fae live side by side, Skylar Thomson must choose between appeasing her driven coach or dating the charming fae who comes to her races. She knows he’s a distraction, but for once, she’s willing to take a chance off the track. Yet when she’s kicked off the team, she struggles to find a way to achieve her racing dream. I almost feel like you should be starting with Skylar rather than with Keil, becuase here is where we learn that the human and fae live side by side. Also, why is she kicked off the team? For being distracted? Because he's a fae? What are the relationships like between the species?

By the time Skylar discovers Keil has been keeping secrets, What's his secret? A query isn't the place to tease she has a target on her back, and time is running out for his kingdom. But he refuses to let her risk her life—he’ll find another way to save Istria. When the queen kidnaps him and poisons the wild fae in his land, What do they have to do with anything? an angry Skylar knows what she must do. But racing a bike is nothing compared to racing a dragon.

HER STERLING FAE is a stand-alone novel with series potential that will appeal to fans of Rachel Morgan’s Creepy Hollow series and Sarah K.L. Wilson’s Dragon School series, and readers who enjoy stories about ordinary girls who accomplish the extraordinary.

I am a freelance web designer with a master’s in Environmental Science and a love for Pomeranians and Manta comics.

Good comp titles! Overall, I think you've got all the pieces, but they aren't in the right places. We need to understand from the beginning that fae and human share a world, what the relationship between the two is, why Keil would seek a human to do this job, and what the secret he is keeping actually is. The threads are all here, but they're not joined together in the braid that you want from a query.