The Shadow General of Demon Lord

Fai is the strongest player of all and considered to be one of the hidden bosses because of her power her character was added in the game as a reminder of once the most formidable and brutal player of all in the game when she is still alive but one day after she died because of her old age she woke up in a different world and was entitled as the Demon Lord's right hand. What would she do in this situation!? I hope you guys would like my story.