User blog comment:B214/DxD Anime gets revamped/@comment-26466163-20160409232349/@comment-3965848-20160410113415

@JackoWacko17 EX is like a 6 part side story taking place around after Vol.18, it's about Issei's kids travel back in time from a possible future trying to stop a future Loki by teaming up with Azazel.

Rough summaries can be found here:

highschooldxd.wikia.com/wiki/User_blog:B214/High_School_DxD_EX

And it's currently being properly translated in someone else blog.