Remember that there is no gravity. There is another game played with a rope which is like volleyball. Your team keeps the rope from hitting your side of the court, and you're not allowed to cross to the other team's side of the court. I imagine the court being shaped like the inside of a peanut shell. Even with all this background, I can't imagine what life would be like for an itzu, so the story stops here.
People talk about aliens invading.
There's even an insurance company in England that sells Alien Impregnancy Insurance. First he'd set up defenses so that no other traveller could invade his solar system. Next he'd probably make a bunch of backup copies of himself to make sure he doesn't accidentally get wiped out. Then he'd take an inventory of what was his, and find us. He's only a meter cubed or smaller, so we wouldn't see him in space.