User blog comment:Crimson and Darkness/Volume 24 discussion blog/@comment-76.65.22.54-20171228065950/@comment-2A02:8109:10BF:B444:0:0:0:3-20171228153914

Meaning:

ExE the Power of Great Red, what it is no Idea? Maybe Issei will turn to a True Dragon God ?! Who knows.

AxA the Power of Issei being the "Child" of Great Red and Ophis. The Power True Power of Issei. HIS very own unquie Power.

ExE could mean something with eternal and AxA with Apocalypse.