I actually finished Music to My Sorrow by Mercedes Lackey and Rosemary Edgehill a few days ago, but...
Anyway, here ends the story of Eric the Bard, unless he's going to show up in the new reboot that he hasn't in 2 books.
This one basically finishes connecting the lines between Jaycie, Magnus, and Ace, as all of their parents get involved in a really complex revenge plan that winds up with just about everyone suffering eternally and deserving it.
In the process, we find out the Elf Jaycie's dad is working with Ace's Dad, a White Nationalist preacher, who's side ministry for rebellious youth sucks in Eric and Magnus's parents.
It's very convoluted, but eventually resolves itself quite nicely.