PFR is an acronym that means Pretty Fucking Ratchet. This word is used when people are describing someone/something as extremely ratchet but don't want others around them to know what they are saying. Therefore they say PFR.
Julianna: that girl is so ratchet!
Shae: IKR! shes a hoe. she'd screw anyone
Sam: shes PFR
Julianna: yeah shes Pretty Fucking Ratchet!
Shae: shhh she's coming!