A strong warrior who works as a mercenary to support his sister Karen. His hometown is Grandshill which is where there is a coliseum and yearly tournament. He is gladiator in the tournament and recognized as the strongest fighter in town. He took care of Karen when she was a child and the two have a close relationship. He is actually a good cook as a result of raising Karen and working as a mercenary.

He is boastful and rough and sometimes has vulgar speech. He is protective of Karen and would beat anyone who hurts her.

He was a wandering mercenary and then became a gladiator in the coliseum, and was called the "swordsman king". He became a mercenary in order to find his father, because his father was said to be a mercenary too. If he found him, he wanted beat him in one blow. After his father's disappearance, Karen's mother died from overworking at raising the children alone. He resented his father for abandoning the family.

(Spoilers)
He was manipulated by Gamuran and joined the Shadow Knights to hunt Growsians. He murdered a number of them, including the chief of Clain village Zemekis. Xenos was also sent to kill Eliotte, and his identity was found. He is son of Belgar and Sierra, and inherited Belgar's ability to control space-time distortions.

Wein Cruz came across Xenos in Grandshill when looking for Karen, and Xenos joined to find her because she had gone missing. He also went with Wein to testify to Burnstein that Wein was innocent about the dam destroying incident. After this, he continued to accompany Wein to find the true criminal.