A ghost? That must have been Danny.

"Scouting?" Heero wasn't really sure what one could do with a ghost either. Up until being dragged to the castle, he didn't even believe in ghosts. That was all nonsense to him. But Danny could fly and get to places no one else really could, so that could be useful. "He can get places we can't."

As for the singing robots, he really had no idea. Haku was really too meek to be of much use besides for sewing. He didn't know much about the other one either.