demon Lord story!

you are the kid in the picture. you're 7,000 years old. you can easily transform into an adult but you actually a kid, in your past life you died at 15 years old, but you were extremely skilled with a sword. you were the youngest warrior of your nation. your job was to defend the queen and King. as war was ravaging, the enemy attacked the kingdom with demons and falling warriors from the past the undead as people were slain. you stand tall but as the powerfulest warrior on the field you were slain. you got resurrected as the kid in the picture