If you're looking for manga similar to 1/2 Undead Series (Light Novel), you might like these titles.
A life spent in a hospital...until one day, a meteor show blazes by. Who is this mysterious boy, Elnath, who searches for Potentiary Crystals, and what do they have to do with the fate of people? New encounters bring with them new experiences, but also new truths from which to flee. And what to do, with these magical girls that know no care? Delving into Minato's character from the anime Houkago no Pleiades, another tale begins.