I prn it ROH-nee (according to the comments section, roh-nee is the Hebrew prn), but I must say that I dislike the name however it's prn.
It could stand alone, I suppose, but I prefer it as a nn for Ronia. If it were a nn for Veronia I'd prn it RAH-nee.
I see it as more of a girl's name, possibly because
Roni is also a nn for
Veronica, possibly because it looks like a feminization of
Ronnie.