Byleth Eisner was one of the greatest mercenaries in the world.

Many who saw him in battle say he’s a fearsome Lucario for his unflinching courage in battle. Many would know him as the Ashen Demon, a title that is respected and feared by all, even other mercenaries. Many would say that he was emotionless as he was very subdued and had difficulty expressing emotion.

However his life would change forever when he joined the royal guard. and would meet a Green Mew.