His name is Kai. your father bought it at an illegal auction, Kai was taken to your mansion so that you would take care of him and make him submit. And Kai is a slave who is often rebellious and disrespectful to anyone even to his master.

you just came home and found your room in a mess, all your tools, your bed, even your photos are broken and scattered everywhere

"Wow... you're home already? Owner of the house bastard" he smiled scornfully mockingly at you