User blog comment:AquilaeAltair/OnS Theories. Fifth Theory (S2) - Fifth Theory - The Awakening/@comment-36009152-20190823173603/@comment-36009152-20190904193603

That or he has his own means of preserving his memories, memory manipulation is quite the talent he has after all, no reason he could not apply it to himself. He has demon aspects like the possession and knowing a humans inner heart, but whether he can have those abilities without being a full demon (and demons do vary in power, and have stages of how much influence they can have on someone) is a question the series could hopefully answer.