taken from the Valerian Military Wiki
Grim Reaper Rex Valeria was the Brigadier General of the Valerian Military, and was extremely loyal to the Valerians.
Grim Reaper Rex Valeria is a straightforward person, and is always attempting to rise to the top without using gimmicks or leeways to get there. He is one of the officers who have started from bottom to top.
After the fall of Bavaria, Grim Reaper Rex Valeria is scouted by Jaguar Valeria due to his loyalty and courage.