The story takes place between the first and second season, where Rimuru confronts the swirling conspiracies in the Coleus kingdom.

The famous cheerful guy, Saikawa had tried to rip off the gloomy kid, Sayama's mask. After that day, he had captured Saikawa's attention and Saikawa had volunteered to teach him for the upcoming examination but with one condition, Saikawa can do whatever he wants with what is hiding under Sayama's mask. He hates it when people touch his bare face, lips and inside his mouth, but he cannot say anything when Saikawa touches them. With the combination between Saikawa's harassment and the awkward mask boy's behavior, this manga will be packed with sexual tension between these two.

"Blue Eyes White Dragon will bring victory" while "Red Eyes Black Dragon will bring the potential of victory". A shy duelist stumbles upon the legendary Red Eyes Black Dragon, with that card in his possession, he must learn to bring out his confidence to duel. (Source: ANN)

The OVA of set to premiere in theaters in 2023.