@Xystus
Power difference, think of each fuck as ropes of magic wrapping around the target. Strong and defiant targets can throw it off if they resist it.
I can tell his plan is to weaken her like a pokemon and then activate all the bindings he has put around her from the earlier fucking. Since she doesn't know about them since they are inactive she hasn't dispelled them.
@Wolvenworks
If I had to guess, golems are predisposed towards being owned. And semen is referred to as a "catalyst" in context to his slavemancer powers. Aka he can enslave without it, but the more jizz they get the easier it is to do.
@Wolvenworks
Just checked the novel and I was right. He can use it without sex but then it is both slow and short ranged. If the golem didn't fight him he could just put his hand on it and take control of it over a day.