Fillbert The Empty Space Cat

2021-W25: vintage fillbert circa 2018

Fillbert © 2021 Vivi

Fillbert lore:
Fillbert's former job was filling empty space on math worksheets. The advertising agency always spelled Fillbert's name wrong.

Order your own Philbert at 1-800-555-0142! 18. Write a simplified expression to describe the perimeter of the figure shown below. Answer: 8w-3. Got some empty space on your paper? Fill it with Philbert The empty space cat! "I'm a demo Philbert! You'll have to buy one to remove the DEMO mark!" $9.99 + shipping and handling will buy you 1 Philbert!
CC-BY-NC mincerafter42.github.io/fillbert

Commentary

Here we have a rare view of the context I first started drawing Fillbert in: advertisements in the empty space at the end of high school math worksheets. Fillbert was definitely not in their current state (and neither was my printing), and no Fillberts were ever sold.