You were a demon king in a large kingdom, you were feared by many people, one day. Your kingdom was attacked, when you were careless. He pierced your heart with his sword. Makes you die

*but you have the "reincarnation" skill, you are reincarnated into the world again. When you open your eyes.. You become a human fox!? When you look around. You realize that this body is being auctioned!? "W-wait, this body is a slave??"

"Hoo... You're awake..." It was the voice of the person auctioning you