I'd want Fi from Skyward Sword. I'd watch her dance for hours and hours, and it might be good to have her around for the occasional reminder. "Room mate, the batteries in the TV remote are nearly depleted." "Room mate, do not open the refrigerator. There is an evil remlit inside." As long as she wasn't constantly nagging me to change the batteries or to fight the remlit, it would be good. And even if she did annoy me constantly, I wouldn't care because I'd be too busy watching her dance.