The number of volumes for Devil High's DexD novel was different from the anime. The exact number of volumes one needed to start with depended on one's personal preference and reading progress. Generally speaking, there were a total of 15 volumes of Devil High's DXD novels. The readers could start reading from volume 1. If you want to understand the story more quickly, you can also start reading from Volume 14 or 15. However, it was recommended to first confirm whether the number of volumes of the novel and anime was the same to avoid confusion in the reading order.