FP - Face painting (Man ejaculates on woman's face)
Facial - Cumming on partner's face
FBSM - Full Body Sensual Massage
FFF - Refers to the strategy of "Find them, Fuck them, Forget them"
FIV - Finger In Vagina
Five-O - A police officer (uniformed or undercover).
FJ - Foot job. Stimulation of the penis using feet and toes.
FKK - Frei Körper Kultur (German brothel / nudist club)
Flake - Flaky Errant behavior, often used for providers who no-show and/or have scheduling issues.
FOB - Fresh Off the Boat (An immigrant who has recently arrived)
FOBU - Fat-Old-Bald-Ugly
FOTC - Fuck of the century.
FOV - Finger Outside Vagina
FR - Field Report
French - Oral sex on either party.
French Kissing - Kissing on mouth with tongue contact
French Without - Oral sex without condom
FS - Full Service, Sex
Full meal deal - Full Service, Vaginal intercourse to completion.
Full Service Intercourse - Sex
FUTB - Finger Up The Butt