WHO could you POSSIBLY mean, "FO'?
Could that person be?:
1. Foolish Orator
2. Fairly Obnoxious
3. Fool Online
4. FAUX-republican Ogler
Here, near or in Atlanta, an "FO" is a "frosted orange" drink at the Varsity.
'Course, to TELL someone to FO (someone should tell RINO-rudy), well, that's another story.