R. J. Anderson 
Wayfarer [EPUB ebook] 

In a time of deadly crisis, Linden alone has the power to save her people.The faeries of the Oak are in danger of extinction, and their only hope for survival rests in fifteen-year-old Linden. Armed with the last of her people’s magic, she travels bravely into the modern human world. Along the way she makes a reluctant allya human boy named Timothy. Soon Linden and Timothy discover a danger much worse than the Oakenfolk’s loss of magic: a potent evil that threatens to enslave faeries and humans alike. In a fevered, desperate chase across the country, Tim and Linden must risk their lives to seek an ancient power before it’s too late to save everyone they love. R. J. Anderson has artfully crafted a world of stunning magic, thrilling adventure, and delicate beauty, where the key to the future is in an unexpected, forbidden friendship.