Ghost

About it
In folklore, mythology, and modern media such as literary fiction, a ghost (sometimes known as a spectre, phantom, apparition,  spirit, spook, or haunt) is the soul or spirit of a dead person or animal that can appear, in visible form or other manifestation, to the living. Descriptions of the apparition of ghosts vary widely from an invisible presence to translucent or barely visible wispy shapes, to realistic, lifelike visions. The deliberate attempt to contact the spirit of a deceased person is known as necromancy, or in spiritism as a séance.

In the game
In Karolina's game, there were one kinds of ghost:

Sheet ghost
This ghost was seen as a sheet on the floating bed, but was then sucked into the vacuum.

In School's game he was seen in a TBA where Legenka Eva TBA

Trivia

 * The ghost of an old man had at the beginning red eyes, but when he get the popsickle, they change to normal white.