I think that is just it, originally his goal seemed to just be to do his job and run the Elf Slave Program, but Autumn's dad has his ear and has been pushing him, that is why they have the rights that they do, then we have Kali's dad, who is also pushing for more rights for elves, albeit in a bit of a fucked up way, and finally we have the player and Lin showing him that being nice to them can at least be as effective at training one of them, if not better if you won.
As far as we know, we didn't do anything illegal there. 'Sui' was already going to get taken from her owner, due to his supposed mistreatment of her, so that is not really an issue, though I will admit, that that was part of the scene that I do not remember too well, I blame Nia and her bat. I might have to go back and watch that again. I honestly doubt that he cares all that much about any particular elf, just that the laws are obeyed and that there are as few problems as possible. But technically, the player just bought them on line, so he did nothing wrong. If the elves had run away and gotten caught, or whatever it was they did to get put up for sale again, that is not anything the player did.
Besides, Cornwall owes the player a boon, and I doubt that Kali's dad nor Autumn's dad would allow him to do anything too bad to the player if their daughters complained about it. With all of this influence, I have to assume Cornwall keeps getting more and more 'pro elf' as days go by. In fact, if the player keeps gathering elves who will, at least officially, obey his every command, and all the elves will do almost anything to work for him, it will only help his case.
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On another topic, while there is already a game called Harem Island and one called Harem World, the sequels to this could easily be Harem Hotel: Island Edition, or World Edition.