There are invisible bugs all over the world. They look like insects without self-consciousness. Bugs attach to objects or humans. They may cause the objects to lose their function. They may also cause persons to act abnormally. Once the bugs are removed, the functions and behavior of objects and persons are back to normal.
When the bug attaches to a container or a bag, the stored things probably disappear.
When the bug open its arms at some entrance or chink, there is an invisible wall to block people from passing through.
When the bug attaches to a person, it mute his sounds partially and randomly. It cause the sentences to be transmitted incompletely or incorrectly.
When the bug attaches to an object or a person, the body can not move, just like being frozen.
It is called the breaker of maps. When it appears, the terrain may get cracks somewhere. Falling in the cracks may just pass through walls, or may reach an unknown space.
Programs having the bug may stop suddenly, never respond the user again.