I am going to use a F.S.O.D on my sexual partner tonight. A dildo, sexual toy that attaches to the head of an individual which is then used to penetrate another's sexual organs.
Stands for Possibility For Significant Other, a person whom you have a crush on, and you know has a crush on you, but you just haven't started datingyet.
A: Have you and C hooked up yet?
B: Naw, we're just P.F.S.O's right now.