User blog comment:B214/Question & Answers 5/@comment-207.96.205.2-20160517060930/@comment-1359322-20160518093811

He's still a Reincarnated Devil as a species. The soul and species are two different things.

"“Even that isn’t known. There has never been a case like this. The current you is a reincarnated Devil who reincarnated from a humanoid Dragon. Except, there is a way to stabilize it. Rather, there has been result. You understand that yourself, right?”"

- Volume 14

So Ise is a reincarnated Devil from a humanoid Dragon.