Flow used as a verb describes the action of making love in a gentle way, trying to please a girl as good as possible and putting ones own needs in second place. Originally consisting of the two words 'to fuck slowly', but as sounding too thugish it was combined to 'to flow'. Pretty popular 'round Staten Island.
First man: - Dude, I totally flowed Shaniqua's booty last night.
Second man: - Gimme a fucking break! Ya can't act like a pussy while pleasing one, ya shlong. Ya ain't keepin' it real, bro!