Ghost (Insert quarter to play)
From Jenny Everywhere Wiki
In one universe, ghosts were eight-bit, digital beings which existed in a variety of colors. They threatened to overrun their world's system, but were prevented from doing so, again and again, by Jenny Everywhere, who, by consuming a particular type of digital pellet, could hunt down and eat the ghosts. Rather than kill them, this forced them back to their cage to rematerialize. After one such defeat, the ghosts swore vengeance on Jenny, vowing to best her one day. (COMIC: Insert quarter to play)
Behind the scenes
The ghosts are transparently the ghost enemies from the classic arcade game Pac-Man.