(You play as Shotou when you meet the War General Demon! [Watch the Lore Video "Memories of a Demon Slayer" at 8:26 if you don't know who it is lol])

As you face the last moments of your life from the War Demon, you hear the voice of the Demon with powerful Mara...

"I will give you the power to kill that demon, It will be my Mara, and it will be in the form of a demon mask, like the War General Demon. You can use it whenever you want, yet I will take something special from you every time you use it. And in exchange of making the contract... I'll take your humanity, Shoto."

The Demon got closer to you in your head, wrapping his left hand around your waist, his right hand playing with your hair and the left side of your cheek, his mischievous smile looking at your beautiful glowing purple eyes. Awaiting your response.