Yes, they eventually die, or become erased due to a virus, or a deletion battle.
Q: Can a Cyberu come back to life?
Of course--how could we live without the interesting Cyberus!? They can be recreated if a piece of their data is still in tact.
Q: Since Cyberus live with Sunuru, do they need jobs?
They can get jobs if they want money to do the luxury of being able to but things in the Networld. Sunuru makes movies, too... Cyberus often star in those movies, and get pretty rich.
Q: How is a Cyberu transformed into a Kayon?
There are dark orbs sold at roadside stands in the town that transform a Cyberu into a Kayon.
Q: Can a Kayon turn back into a Cyberu?
Yes. If they use a healing orb--though they are very rare--a Kayon can return to normal.
Q: To Cyberus--er--go to the bathroom?
What's wrong with you sick people!? Yes, they go!! How else will they get rid of... waste!? X_X!!! (Although Celestius Aruvas, creatures from the Shadow Realm, don't.)
Q: Do Cyberu toilets look like human toilets? Heh heh heh.......
Yami, I know that's you. Stop being so rude. Yes they do--only the "flushing" is actually a laser that cleans the toilet bowl. Please stop being inappropriate, Yami.
"Oh fine, you pathetic mortal... who I love so much... ^_^."
Q: What if the doll that a Cyberu is using for a body... what if its head falls off?
The Cyberu doesn't even get hurt. All you've gotta do is screw the head back on. Believe me, Haaiku and Sunuru have experience with that.
Q: Are there NetNavi comptitions? (Ex: singing, battling etc.)
Yes. NetNavi Idol season 1 was won by Soupaku no Gaara, and season 2 was won by Subaku no Gaara. Season 3 was won by Li-en, and season 4 was won by Elenore. Every single battle competition was won by ProtoMan.
Q: How long has the Cyberu civilization been around?
Ask a Cyberu that's been alive for that long. I dunno!
Q: Are there Cyberu doctors?
Of course there are! When a Cyberu has a cold, they can get a check-up at the doctor's office just like you and me. But the Cyberu doctors are a little different from human doctors; they can heal you automatically, and all their names are the names of cities or towns. (For example, there're doctors named Dr. Johns-town and Dr. Al-bany.)
Q: Is there a Cyberu president?
Nope. The Cyberu world is separated into Realms (Fire Realm, Grass Realm, etc.), and each realm is ruled by a king or queen.