Here's why:
* Visual Representation: "Zzz" is a simple, iconic way to show that a character is asleep. It's a visual shorthand that everyone understands.
* Onomatopoeia: "Zzz" is an onomatopoeic word, meaning it sounds like the noise someone makes when sleeping. This adds a layer of realism and humor to the scene.
* Humor: The "Zzz" sound can be exaggerated or used in funny situations, like when a character snores loudly or sleeps through a chaotic event.
In short, "Zzz" is a fun and effective way to convey sleep in comics.