The Credit Card System Is the system dictating which credit cards can be used in either Sop Pong or Pong Sop.
Father's credit + Mother's credit=
'Baby's credit card= (Baby is either visa or mastercard depending on parents)
Sister's visa card or Brother's visa card
Sister's visa =Mother's visa
Brother's visa =Father's visa
Father's visa = Grandfather's visa
Mother's visa= Grandmother's visa
and the cycle continues.
Sop Pong cards = Any female card, or OTM
Pong Sop cards = Any male card, or OTD
Sop Pong= Father's visa card OTD
Pong Sop= Mother's visa card OTM
USING THE WRONG CARD IN A COUNTRY WILL RESULT IN DEATH.