User blog comment:B214/Volume 22 spoilers/@comment-73.46.6.122-20160819203110/@comment-197.113.24.52-20160822005840

The thing about Issei who can't possibly become a Maou because a stupid reason like "he can't have an harem" seems unlikely, after all the most important for a Devil to become a Maou is both power and popularity, and of course the achivements the said devil accomplished, If Issei wants to become a Maou then there's visibly nothing to stop him, and even if he has an harem while standing on the upper echelons of the Underworld I guess there's no problem since he has the support of his own people, and strength, After all there was once a Maou who was dressed and acted as a Magical girl...*sniff* Levi-tan is no longer with us *sniff*