The Labyrinth: Visitors

Under most circumstances, the kaijin would pretend to be Zhen Liu's literal puppets.

Thank to their varied designs, physiques and the fact that most of them were made literal chunks of stone and metal, the kaijin were able to maintain this façade up to this very day. Even when people came to see Zhen Liu sparring with the kaijin, they just assumed that he was practicing his puppet control techniques. However, maintaining this cover had one surprising drawback: obvious culpability.

The Zhen Clan had become so accustom to seeing Zhen Liu "use his puppets", that it had gotten to the point that when the kaijin would walk around undisguised, they just assumed Zhen Liu was nearby doing something else. 

However, this meant that in this one, very specific instance, where their lord's cousins were the antagonistic force, the kaijin showing up in their normal forms would lead to a cascading ripple effect that would be more trouble than it was worth.