there was a girl in psychic academy who was called orina, so i guess it's not too rare name...

EDIT: well, screw that half assed explenation, i've got some semi-real information from a semi realiable source.

according to Hanaotoko volume 2 chapter 18 page 082 translated by manga screener, in the 7th of july there's a festival in japan that celebrates the meeting of Orihime (vega) and Hikoboshi (altair), and while the festival isn't relevant to the topic, it's now clear that orihime is an acceptable name, and is probably somehow related to stars, and had i have any real knowledge about astronomy in english, i would've been able to confirm it.

oh, and by the way, can someone check up what's orihime's birthday? is it also the seventh of july?