His fantasy was rape and bondage so I don't know about that. People who do that sort of thing tend to have a real short attention span when it comes to their victims. There has to be another reason for her being kept alive. The first rape was supposedly a month after she was kidnapped, which doesn't fit with his fantasy as far as we know. If he was acting out his fantasy, he would have done it immediately and probably got rid of her after a week or two. I think when they dig deep enough into this guy's mind it is probably going to come down to some kind twisted family thing. A lack of love in his childhood, an effort to synthesize his vision of an ideal family using innocence as his building material.
i believe they span the first charge from the day she was kidnapped to the next month, so it could have been anytime in that first month, right?. i have a hard time believing he waited at all before abusing her.