Who is Horst the Cat Man from Geek Love and what is their importance?

Horst is one of the constant characters in the book that is behind the scenes, yet plays an integral role in the family's life. He is actually the one that saves their legacy after the fire by protecting the journals and notes about the cult, while selling off anything of value in the vans. After the children are shot, he helps to bring them home. He is the quiet man standing over the Binewski family, looking out for their needs in a selfless manner.