Sumo’s former little big man, Mainoumi, taught his first class Wednesday as a part-time lecturer at Teikyo University in Tokyo.

Mainoumi, who now goes by his real name, Shuhei Nagao, reached the sport’s fourth-highest rank, “komusubi,” during a 10-year professional career and is lecturing once a week on “sociology from the viewpoint of sumo,” the school said.

Known during his career as the “technical department store” for his trickery and array of techniques, which often brought down much larger opponents, the diminutive 32-year-old wrestler retired from the sport after last November’s Kyushu tournament.

Nagao received his teaching qualifications from Nihon University and almost became a high-school teacher before turning his attentions to a professional career in the sumo ring.