I know they're people. Soubi and Natsuo have likes, dislikes. They have desires and wants and needs. They may love their sacrifices, but Natsuo has called Youji stupid. Ai from Breathless has gotten angry, needing to be calmed down. Even the zero girls, went to school and had personalities different from Natsuo and Soubi. If you weren't people, if you weren't individuals, you would all be exactly the same. You, Soubi, Natsuo, Ai, all of you, would be exactly the same because you wouldn't be people. Soubi wouldn't have parents, he would be created in a lab. But even then, Natsuo and Youji care for Nagisa-sensei.