In witch version of the game are you playing? Did you use an ancient save? if it's the cas you can start a new game and use the shortcut content or skip button, it will help for this bug I think.
Viewing post in Tower of the last Demon (AN ABDL RPG) Ongoing comments
i used ver. 0.08 and i used the skip button in the corner after completing the first dungeon and i get to the mirror where you see the commander i can't do anything and the message box in the bottom is blank and i get stuck in it. I figure it out if i click too fast through i get stuck now it works :)