Our protagonist, Willow, was born princess of the magical realm of Mistolear but sent to Earth as a baby; we open with a portal being opened to return her to Mistolear. A powerful Fay has pitted the kingdom against its neighbor in a live-action chess match, and Willow finds that her growing up on Earth has given her unexpected powers and skills to use in unexpected ways, both here and in the sequel.
There was a lot I liked about this duet, including its use of the Fay, its chess references, and its twist on portal fantasy by having the protagonist really have been born off-Earth in the first place. But as I read it, I found myself getting tired of the protagonist's out-of-place modern attitudes. For example (at the start of the second book), why must she insist on sunbathing in the castle courtyard wearing an Earth-style tank top? The contrast between Earth postmodernism and fantasy quasi-medieval is interesting in the abstract, but as it's presented, I find myself sympathizing less and less with my own world.