'Hir' and related nominative 'shi' are seen most often in internet-presented stories involving (the usually pornographically inclined presence of) hermaphrodites or those capable of changing their sex with ease.
We know hir well; shi cannot surprise us any more.
He seemed perfectly alright with hir cutting him in line.
Just tell hir that you don't have the time right now.
Yea, i remember, 'hir'.