Even after he had fixed his Soul Impurity issue, Arthur still did not participate in the ongoing battle for Plomux.
This time, the cause was his lack of interest.
He left the Gozonian Army to continue bullying the Aramisians and headed deep into Plomux. Evan was bored of the constant fighting so he tagged along for the fun of it.
Since they possessed features that would make them blend in with the Aramisians—Arthur's Divinity and Evan's Draconic Human nature—they could easily enter Plomux-Central with the Aramisians none the wiser.
As for why they came here, there were two reasons.
First off, they just wanted to explore.
Secondly, they were here to meet up with Beatrix and Artemisia who had just silently assassinated the great-grandson of a prominent god King of the Aramis faction.
Evan could not hide his surprise upon discovering Beatrix's 'side job' on Aramis, hunting down the descendants of god Rulers her mother didn't like.
