Ren Algua is a Wizard of the Omicron Seal Guild and one of the Kenshōgen (lit. Great Swordsman of Fiore).
Ren has short, tufty blue hair, and dark eyes. He also has pointed, shark-like teeth and wears square, black-rimmed glasses connected to ear protectors, a blue pin-striped shirt and camouflage pattern pants. Also, he wears his forehead protector on the front of his holster which he uses to carry the Sakana Sword. The sword itself is wrapped in bandages leaving only the double hilt visible.
Despite his membership in the elite Kenshōgen group, he is a shy individual and seems to lack confidence in his abilities. He seems to be more confortable around his guild mates, but just barely. He has alot of admiration for his guildmate, Genrei Tekken for his status as a Wizard Saint.