-ㅂ네까

Etymology
See.

Usage notes
While some North Korean defectors claim that this is an exaggerated or even a made-up form, most defectors are Yukjin or Hamgyong speakers from Northern Hamgyong or Yanggang Province, and thus use,, or  forms instead. Among defectors from Pyongan speaking areas, some appear to consider this form old fashioned or quaint.