After he finished 'apologizing', one more person entered the room and stood behind the Shogun. He was a slightly old man, his appearance average and easily forgettable yet the moment Arthur saw him, his pupils shook and his aura became momentarily unstable. Once could see that the years took a great toll on the man's tired face, in fact, he was pitifully weak in comparison to the woman or the shogun yet here he was, dutifully serving someone he considered as his master and leader.
Arthur's memories drifted to the past, just when he and Lucy got separated. The Emperor's castle got invaded by a bunch of monsters called Khin but were in fact the Cthulhu. There was a man who guided Arthur into their world yet he tricked him and teleported his people and himself, causing the world to crumble.
It was one of the few times Arthur almost died were it not for Anastassia's intervention later, he would have been killed by Bucama.