It is not clear in the film but something about her step-son demanding that she do certain things in order to keep him from telling his step-father something she does not want him to know. Ya know blackmail! Things like making herself cum with her Domi and giving him a JOI and letting with film it. Fucking her doggy. And finally filling up her pussy with his huge load. Either way, she seems to be loving the sexual attention from her step-son.