Stam is Tachihara Michizō. A hunting dog.

He joined Astray because he felt he was an outcast due to him being too kind and pure hearted. He plays a role of bait in Astray.
He keeps the fact he works for Astray a secret. Seeing as Astray’s goal is to overthrow the government, and the hunting dogs is a government organization.

Only he and Jouno know about the fact they both work for Astray as spies. They keep each other in check and always have each others backs. Making sure no info about Astray