A book involving castles, invisibility, a monk, evil

[Dhillon]

I read this book prior to 2007 so it has been a while and I've forgotten most of the details. I can't remember if I discovered it in my university library or city library but it was in paperback. It would most likely fall under Young Adult Fiction, Fantasy, Children's Fiction (?), Adventure.

It has seven(?) castles/castle-towns and those place have names like those of the castles in Europe or the ones in Game of Thrones. In fact, I can picture that book being set in the same sort of geographic and time setting as Game of Thrones. At a certain point, invisibility comes into play. I believe one of the characters used it to escape from danger, much like the way the ring works in LOTR. He/she went invisible and fled on foot in a hilly area. I also remember there being a monk and a battle with some kind of monster/demon. I think it had wings and could fly.

There was a scene where the protagonists home castle-town was hosting a party of knights from another castle. There were some politics involved, kind of like in The Game of Thrones when Robert visits Ned Stark.

One of the names of the castle-towns is on the tip of my tongue but I just can't remember. It is incredibly frustrating and I've been trying to remember the name of this book for years now. I discovered this site and am hoping one of you will be able to help :) I know its not much to go on but any help will be greatly appreciated!

[Lobstergirl, au gratin]

Dhillon, are you still looking for this or did you find it?

[Dhillon]

Hello! I am still looking for it. Unfortunately, I haven't had any luck finding it.

[Kate]

Dhillon ~~
You can "bump" your thread every month or so. This pushes your thread back to the top of the folder instead of languishing here on page 43 where fewer eyes will see it.
Good luck!

[Kris]

Dhillon, who is the main character?

[Lobstergirl, au gratin]

Still looking now?

[Erin]

Reminiscent of the Memory, Sorrow, and Thorn series