Mr. Williams is a minor character mentioned in File Under: 13 Suspicious Incidents, in the eighth incident, "Twelve or Thirteen."
He competed in the Ethan Frome Sled Race for several years. He eventually married one of his competitors, Miss Herman. He was the third sledder in the race where the portrait of Gary Dorian was stolen.
He and his wife continued to live in Stain'd-by-the-Sea after the economic collapse, working at the distillery.
- His name, as well as the names of his fellow competitors, is a reference to "Willow Poem" by William Carlos Williams.