I have many plans for my ninja day... Most of it is going to work dressed like a ninja without the hood. And getting home and watch NInja movies... I have a few in mind... What is your guys plans for the Day Of The Ninja. ninjaday.org, has independently declared December 5 as International Creep Like a Ninja Day. Other possible names include Stalk Like a Ninja Day, Sneak Like a Ninja Day, Move Like a Ninja Day, or simply Ninja Day. The last of which redirects to the official page). According to the official website, this site and others of its kind are unrelated to Ninja Burger or the original Day of the Ninja website, although their efforts are supported.