"...That is why we ultimately couldn't find our mentor anymore." Lena began, holding the diary, she looked at the deity before her: "Esteemed Nameless, did you finally purify our mentor?"
"Yes, I was powerless against the corruption on him. I could only ensure that the forces of Subspace couldn't corrupt me and my beloved, but your mentor... in his final hours, he was becoming more insane, more forgetful, like your fellow student here. Ultimately, as per his request, I purified his soul, sending his shell to that star," the seemingly young deity finished speaking as their ceiling turned transparent, letting the sunlight cascade down and illuminate the underground world.
"Then, Your Highness, may we know who Malin really is?" Anna looked at the Nameless before her, never before so urgently wanting to know the truth as she did today.
"He is Malin, a stubborn soul," Nameless's answer was very simple.
So simple that it couldn't really be considered an answer.
