User blog comment:B214/Question and Answers 2/@comment-187.209.0.247-20140225180954/@comment-187.209.0.247-20140225182802

Well, Irina revealed that the desire of issei when he was kid was to become a hero, and during the light novel issei has been perturbated by the fact that a Demon Can not become a Hero, since he met Caocao First Time in Kyoto, and even Indra and Rizevim Livan Lucifer repoint that fact "A Demon can not become a Hero", and even Rizevim point that issei in one of the existences more dangerous of the planet.

So maybe the author is planing to do something with that, a Demon-Hero, or maybe something more.....