Sho is a former Osiris, then Ra, and now Obelisk student as well as Judai's best friend. A decent duelist, though hindered by a great deal of self doubt, Sho's journey toward strengthening himself provides sharp contrast to protagonist Judai's active determination. Sho is often a "comic relief" character, partially due to him being very nervous a large portion of the time, in a sharp contrast to Judai's optimistic nature.
(Yu-Gi-Oh! Wiki)