Really nice and fun game!
I'm not usually a big fan of turn-based battles, but I enjoyed your demo a lot. Every character feels unique and the way they compliment each other works perfectly. Characters are very likeable and interesting enough to make want to know more about them. Art is charming, sound and music always seem to fit perfectly, and everything seems very polished so far.
A couple of suggestions I could make are that being able to jump to the first skill on the list when pressing down at the last one (and viceversa) would help a lot to speed up the navigation during battles. Also it took me a while to figure out how to close Avi's thoughts and Party Talk's windows, but I can't think of any idea to make it more obvious either.
Only issue I had with the demo is that the game gets stuck during the final battle, after Mizar changes patterns (he won't attack me and I can't attack him either) so I couldn't really finish the missions.
Hope to see more of this project soon, because I really liked it!