That Time I Got Reincarnated as a Slime OAD

The That Time I Got Reincarnated as a Slime OAD episode bundled with the 13th manga volume focuses on the first-ever sumo tournament held at Tempest, an idea suggested by Rimuru. The event is a key part of the outdoor training at Ingracia Kingdom's Freedom Academy, where Rimuru teaches students. In the annual competition, Rimuru aims to win the prize money, but faces a challenge from Jeff, an honorary teacher who views Rimuru as a rival. The competition is interrupted by an unexpected attack.