The Zippertile is a NPC found in the Number World. It is located in the southeast corner of the Numbers world, to the right of the door with 0's and 1's in front of it.
At first, it is similar to the other zipper wall decorations in Number World, however with an unhappy expression. Their appearance is determined by random chance. If it's in the happy state, the player is advised to wake up and return until it changes.
When using the Knife on it, Zippertile makes a surprised expression and opens its zipper to reveal a red-rimmed hole that gives entry to the The Stairway, where KyuuKyuu-kun can be found. Their mouth then smiles again and oozes a red liquid that borders the entry hole.
Entering the hole reveals that part of them can still be seen from the other side, however with some slight changes. The left eye is now round, not square and they seem to possess a small pink nose.
It does not react to any other Effects, however as it screams when the Knife effect is used, it is considered "alive" and not just a wall decoration.
All Zippertile NPC's/decorations have one red/pinkish eye and one black eye. All rows of zippertile have an orange arm and foot at opposite ends.