Revealing himself to be a Dual Knight, Long Hao Chen triumphs in his match within his temple and advances to the finals. But before the grand finals can begin, ranking matches are conducted in each temple to determine the strongest within. During the rankings, Hao Chen is injured, enraging Sheng Cai'er and driving her to seek vengeance for what happened to him. Her actions cause a fight between the Knight Temple and Assassin Temple, only to be subdued after a shocking revelation—that Sheng Cai'er is a Reincarnated Saint. The finals for the Demon Hunting Team Competition begin with the division of the sixty remaining participants into six groups. The top sixteen participants are then further pitted against each other to determine the top three. Each of the top three will be rewarded with a spiritual stove and the right to pick their teammates. In order to become a knight that is capable of defeating the Demon Lord, Long Hao Chen must strive to be first in this competition so he can select the best teammates to give him a fighting chance.

The OVA, bundled with the special edition version of the seventh manga volume, will tell an "other side" story centered on Mafuyu Satou and Ritsuka Uenoyama that wasn't featured in the movie.

Since childhood, Haruka Kotoura's classmates have seen her as a creepy and monstrous person. This is due to her ability to read other people's minds—the same ability that drove her parents away, leaving her alone with her grandfather. As a result, she has grown accustomed to the bitter treatment by the people around her, becoming completely cold and unsociable to others. However, everything starts to change when Haruka transfers to a new school. While most are off put by her as usual, she meets Yoshihisa Manabe, who finds her power astonishing. Yoshihisa then proceeds to befriend Haruka, promising to never leave her no matter what happens. Haruka's new experiences of social belonging thus begin, meeting new friends and learning to open herself along the way. [Written by MAL Rewrite]

To kick off the season, a special episode titled "Digression: Diablo's Journal" will release on March 30, recapping the events of Season 2 from Diablo's perspective.