The last fallen moon / by Graci Kim.

Enhanced descriptions from Syndetics:

"Graci Kim does such an amazing job of blending Korean mythology into the modern world, I am now wondering how I ever lived without knowing all this cool information."- New York Times #1 best-selling author Rick Riordan

For Riley Oh, life as the Godrealm's last fallen star is not all it's cracked up to be. Her new divine heritage doesn't even come with cool magical powers; half of her friends and family (including her parents) can't remember her; and to top it all off, the entire Gom clan is mad at her for killing the Cave Bear Goddess and stripping away their healing abilities.

But when their anger boils over and a group of witches curse Riley's home, she knows it's up to her to restore magic back to her clan - even if it means sneaking into the Spiritrealm.

Luckily, Riley has some backup. Along with her sister, Hattie, Riley meets Dahl, a heaven-born boy with shockingly white hair and a fondness for toilets who might not be telling the whole truth about who he is. Together they'll fight vicious monsters, discover dark underwater worlds, and race to save the land of the dead from a fate that no one could have foreseen.

And this time, Riley won't let anything get in her way. Because she can't shake the feeling that something terrible is coming their way - and the gifted community is going to need all the powers they can get.