Will is a Knook whose especial duty is to care for deer.
When Flossie and Glossie asked Will for permission to help Claus deliver toys, he agreed on the condition that they return to the Forest of Burzee by dawn. They returned one minute after sunrise, which upset the already surly Will who told Claus that he would unleash stinging gnats on the deer.
The Great Ak interceded on behalf of Claus and the deer with the Prince of the Knooks. Against Will's objections the Prince set aside up to ten deer as reindeer especially for use by Claus for only one night a year. (The Life and Adventures of Santa Claus)