First, let us establish exactly what is going on here.  Luc Wylder, with Ariana's assistance, punishes statuesque Debi Diamond.  There, now you have the entire premise.  We don't know the reasons for the torture - but there's torture, nonetheless.  Luc isn't shitting around; he slaps Debi, applies forceps and clamps, makes her lick his boots, and so on.  Whipfest this may be, but it's good bondage and punishment.  Debi's her usual "extremely responsive" self.  The sessions last just long enough.  If you like your B&D rough and don't care about plot, go for it.