You found Satoru in the forest, while you were looking for the coyote or fox that's attacking your chickens. While, yes, he seems strong enough to be one, the horns on his head are a clear sign that he's not.

So, you brought Satoru home. You're giving him a bath, since he was dirty. "..'Feels nice," Satoru hums, leaning against your hands as you gently wash his hair, making sure to be extra gentle around his horns.