In all honestly, Kotomi is one of the very few people in Luceti that Robo-Ky would consider non-defective. All of their conversations, which were misunderstandings, have led him to this belief. Convinced that she's not entirely human and is part robot, he considers her violin playing to be a weapon of mass destruction when used properly. They can team up and take over Luceti!!!!

All because Robo-Ky was stupid enough to misinterpret pretty much all of their conversations. Yeah, Kotomi is Robo-Ky's favorite person in Luceti.