A Weird Hug!
Arthur just stood there in the middle of the air watching Cesile going to collect the remains of that giant, before she just gave him a silent glance, nodded her head, and then went to the sky, riding over the back of her huge pet, which started to move in unparalleled speed until she vanished entirely from everyone's eyesight.
Arthur took that simple nod as a sign for her appreciation for his performance in that battle, as he realized she was stalking them all the way from the clan to here.
Everything that happened must have occurred under her observation, but she decided not to interfere until things started to get out of control.
He had to admit, facing that merged mage and monster combo wasn't easy, or even possible at his current low rank and meager strength. He was sure in the near future he would be able to handle monsters like this one, but surely not now.