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1.
KFN
Simple coded abbreviation of 'Keen for Nailing' used in busy areas with multiple females in close proximity.
KFNAB is an extended version if one is very keen or 'Keen for Nailing as Baalls'
'Mate she was KFN last night, she wanted it right up the ricker'

'Carter was KFN last night but didn't get any action, standard, what a schlad'
by Harry the Hatchett October 04, 2009