There was a reason Roy noticed this.
He acutely noticed that when the naaru A'dal used Holy Light to fight against him just now, a very small portion of the radiation of the Holy Light power was directed at Auriel on his shoulder.
Although A'dal had done it very secretly, and the impact of the Holy Light was not only very weak but also quickly stopped after reaching Auriel, she didn't know that Auriel's body and Roy were almost one because of the symbiotic contract. Roy's power was also circulating in Auriel's body, so even though A'dal's probing was very careful and cautious, he discovered it immediately.
Roy didn't notice A'dal's intentions at first, but he suddenly understood.
A'dal seems to want to try to awaken Auriel!
In other worlds, the representative of the Holy Light was angels, and in this world, the representative of the Holy Light was the naaru. So in fact, the naaru could be regarded as the angels of this world.