Yahiko actually understood that Charlie might not really have his best interests at heart.
After all, when Charlie had first come to Japan, Yahiko had had conflicts with him, and he had even had a very arrogant attitude at that time as he thought that it was only right for this young man from Oskia to grovel before him.
After Charlie had put him in place, Yahiko finally realized how difficult it was to mess with this young Oskian man.
The reason why Charlie had later treated him more politel