The former commander of the now defunct 7th Squadron of the Demon Slayers. After surveying the region of Atharva， Rhoa discovered many artifacts of legend left behind by ancient technicians， managing to also deduce their purpose and functionality. Many of the techniques used in the Hall today are products of his work and research， while the establishment of the Summoners' Research Lab can also be attributed in part to him. It is said that Rhoa and the commander of the 6th Squadron of the Demon Slayers got along like cats and dogs， and their feud is so famous that it is often referenced to this day.