Donut's Diary is an item that appeared in "The Liar Ball You Don't Want". It has the same cover as Creatures of Goiky, suggesting that they are the same book. As the name implies, it is a book owned by Donut expressing his thoughts and findings. It is currently in the possession of Loser inside the Liar Ball. As of "Get to the Top in 500 Steps", there appear to be sticky notes in some of the pages, as Loser must be taking note of some of the interesting finds in the diary.
- "Dear Diary, I regret to inform you that I discovered something very horrific about Bomby today. You see, he—"
- "Why do I have filling, but also a hole?"