A tragic ordeal befalls two sisters who end up living with their stepfather after their mother remarries. A penis that was inserted into the older sister’s vagina is then thrust directly into the younger sister’s throat—P-to-M incest, moving from the younger sister’s vagina to the older sister’s throat. Simultaneous throat-fucking training for both sisters and a relentless series of the most extreme deepthroat sessions. Forced to serve as sex slaves with no respite, subjected to nonstop sexual servitude day after day—what will become of these women…?