A colloquial term for an unscrupulous, duplicitous self serving and/or untrustworthy individual, seemingly charming and the proverbial 'nice' at first, but to be trusted at your peril, for they will strip you of everything you own, and happily and without a shred of remorse, renegade on any and all agreements you have made with them, no matter what the cost to you, and no matter how devastating the consequences of their actions, so long as their despicable actions have no effect on themselves.
This term has latterly and colloquially been replaced with 'Pulling', but the original 'Pullen' is still used widely in those places where its original form was previously used and its original meaning and origin remain understood.
You haven't trusted that Bradley have you, I'm sure he's pullen a fast one.