I am Rimuru-sama's faithful shadow. I will perform any instruction that I receive.Souei
He is Rimuru's faithful shadow and the leader of the Shadow Squad of Tempest's Department of Intelligence. Later on, after Benimaru's evolution into a Demon Lord, he was treated as his shadow instead, perhaps as a means to preserve their long-lasting relationship during the Ogre days.
As an Ogre, Souei had a lean yet muscular figure with a height nearing Benimaru's Ogre form. He has dark skin, dark blue hair and, blue eyes.
In the Anime, from his forehead, protrudes out a single (two in the Web Novel) white (black in the Light Novel and Manga) horn and a blue eye-shadow on his lower eyelids. His skin also had a bluish tint which made his look overall grayish. From the corners of his mouth, also peeks two white canines, which further complements the already vicious and angry Ogre appearance.
His hair is straight and is of medium length, where his bangs cover his right eye most of the time. His clothing is tight-fitting, possibly due to his fighting style relying on speed and agility.
After evolving into a Kijin, Souei shrunk to that of 190 cm and with the appearance of a lean young man in his late teens. He looks incredibly calm and collected, that goes well his confident personality and is all in all a beautiful man (ikemen) with a different air around him.
Thanks to Shuna and co., Souei received a brand new attire matching his dark blue color scheme that isn't too tight nor too fluttering to get caught in sharp objects during his espionage missions.
He's strange. After being appointed as a ninja, he took the position a tad bit too seriously. His presence radiates composure and unblemished strength. He ruthlessly doesn't interpose personal feelings.
Being commanded fills him with the highest of pleasure.
Souei has an eloquent tongue to match his good looks.
A time of peace had continued for a while. Symbolizing strength, the Ogres had no opponent in the forest. Even lesser dragons had not caused any commotions. He had thought that peace was a good thing. However, they also wanted to use the skills they have obtained, such was their earnest wish. Then, they were attacked by the Orc army. He could do nothing at all and left without avenging his lord and fallen comrades. Under the new Lord, Rimuru, he was given the name Souei, and an opportunity to avenge his former lord.