User blog comment:Mnzombie/Issei's Peerage/@comment-76.91.15.95-20130509211353/@comment-9297146-20130510020650

The volume 13 afterword, it sais how he is thinking about a Millicas spin-off after a few years timeskip. The rest is spread out over a few volumes, basically the author jokes that it would be pretty pathetic if Issei graduates college and he still hasn't gotten laid, another one he lists the top strongest in the DxD universe and there won't be that many people for him to fight against and so on.