Other Gay Posse... Typically when one straight person within a group has two separate sets of gay friends, they may refer to the set not present at the time as the O.G.P.
Dr. Dre:
"who d'u think brought u the O.Gs,
Eazy-Es, Ice Cubes and D.O.Cs
Snoop D-O double Gs, (s-n-double-o-p-d-o-double-g)
And the group that said muthafuck the police."