User blog comment:Jopjopjop/Volume 19 Quotes / Spoilers/@comment-24098614-20141104025924/@comment-1359322-20141104132613

Well there's a factor differentiating between this two series, DxD focuses on myths, so there's a limit to how much the author can expand on that. Index is an original story, it just focuses on two different parts of a world, the author can expand on that as much as he wants without much concern.