She start running like FLo-Jo
Running is slang for having sex with a lot of people. The girl started running like Florence Griffith-Joyner, the fastest woman of all time, (track wise).
It should also be noted that Florence Griffith-Joyner was raised in the famous Jordan Downs Housing Projects: a 700-unit public housing complex in Watts which may relate to where the girl in the story was raised.
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