The episode bundled with the 13th volume is about the Sumo competition that held at Tempest for the first time, suggested by Rimuru. The three-part OVA bundled with the 14th, 15th, and 16th manga volumes is an original trilogy written by Fuse. Rimuru has been teaching Shizue's students at Ingracia Kingdom's Freedom Academy. The time has come for the school's annual outdoor training event, where the students will test their combat skills in the field. Rimuru is determined to win the competition and take home the prize money, but he is challenged by Jeff, an honorary teacher who sees Rimuru as a rival. The competition is underway when suddenly an unexpected enemy appears!

Jubei Kibagami wanders feudal Japan as an itinerant swordsman-for-hire. After a past betrayal left him masterless, he has no more patience for warring political factions and their schemes. Unfortunately, both past and political intrigue collide when he meets and saves a female ninja named Kagero from a man with the ability to make his body as hard as stone. The sole survivor of a ninja clan, Kagero continues her team's last mission: investigate a mysterious plague that wiped out an entire village. Jubei wants nothing to do with this, but the stone-like man's allies, a group of ninja with supernatural powers known as the Devils of Kimon, make that option difficult. To make matters worse, a government spy poisons Jubei, promising him an antidote if he can unravel the true intentions of the Devils of Kimon and their connection to the plague. The trail leads to shadow leaders, a plot to overthrow the government, and a man that Jubei thought he would never see again.

Thanks to the Fruit of Evolution, Seiichi Hiiragi's amazing new life in another world allows him to meet dependable allies and create formidable spells. His abilities catch the attention of Barnabus Ablitt, the principal of the Barbador Academy of Magic, who invites Seiichi to become a teacher at the institution. Coincidentally, Seiichi's classmates from Earth are enrolled there, which will lead to an awkward reunion if he is to meet them. Behind the scenes, however, an enigmatic cult called The Great Devil Order devises a sinister scheme to resurrect their deity and sacrifice the students of Barbador to hasten the process. As Seiichi's power is second to none, it is up to him to protect not only his friends but also the entire world from the looming darkness.

A comedy about a family of old-fashioned samurai living in modern-day Tokyo whose young son has to head out for an important date.