User blog comment:B214/Talk About What You Want! 3/@comment-37.231.35.244-20141112075043/@comment-1359322-20141112231509

Rias and the girls sealed that gender Raygun already. When Ishibumi wrote the first SS, on that Raygun, he just thought it would be fun to see the ORC (minus Issei) in opposite gender. But then few fans started to speculate on Kiba having a gender change, so Ishibumi made a second SS on the Raygun, to have it sealed forever, and in a way end any confirmation of Issei x Yumi. Probably because Ishibumi wants to go ahead with Yuuto x Tsubaki.