Hunter actually trained him, until at some point he realized that Sterling is not like Hunter or Drew, Hunter initially showed him how to seduce women and other things, when Sterling returned home, and immediately realized that Sterling was a threat to Hunter and interfered with his plans. after all, this is a confrontation, since Sterling's father lost, then Sterling can protect the family... now the question is, will he keep the harem without Hunter? I think yes, at some point we see all the women’s love for Sterling, since Ophelia already knows who her son is fucking with, this is already a good sign even without Hunter’s drugs.
Hunter just pushed them more into the intimacy that he wanted for himself, and of course Sterling got them, he was in the right place at the right time and prevented debauchery... then it will be interesting what kind of fun awaits us