Erston Outway or simply known as "Gaius", was the main antagonist in Tales of Xillia and became a major character in its sequel.
He is voiced by Ryōtarō Okiayu in the Japanese version, and by Travis Willingham in the English version.
Tales of Xillia[]
To see what Gaius was like as a villain, see here: Villains Wiki Page: Go Here
Tales of Xillia 2[]
In the game, Gaius and Rowen were first seen in Duval. They learned from Ludger, Elle, Jude, and Leia about the fractured dimension they just went through. It was shown that Gaius was investigating Elympois' activity as simply a man known by his real name, "Erston Outway". Unlike the others, Gaius apparently isn't too fond of technology.
In a sidestory, Gaius, Ludger, Elle, and Muzet ran into a group of Elympion boys. Tanner, however, didn't approve of their relations with Razie Maxia and had a group of townsfolk attack them at the Residental Quarter. Later, Kyle, Tanner, and the rest of the gang suggested that Giaus would go with them on a trip to Razie Maxia. While sightseeing in the Sapstroph Deepwood, Gaius, Ludger, and Muzet had to help fight off berserk monsters. Afterward's, the whole group took a picture together and then Gaius was given the camera afterwards.
Back at Marksburg, Kyle was accused for killing a soldier. During an interrigation, Gaius' true status as king was revealed and that he couldn't bring himself to act for a single person or that it would tarnish his kingly status. While Kyle ended up on probation, Ludger insisted that Gaius would keep the camera that was given to him as a personal gift.