Three people here seem a bit out of place, powerwise. Three immortals, one ghost-princess, one Yuuka (no further titles necessary), one reality warper...and three musicians?
It is, actually, but that is just my opinion, although I do recommend it.
I'll second the recommendation. The choice of characters makes perfect sense if you've read it. Make sure and start with volume 1 first though, think there are 5 total.
Plus, adorable child Yuuka on the moon. Nuff said.