Easter eggs are hidden secrets or jokes in games. There are easter eggs in CBD.
Manager Easter Egg Edit
Far right of the back door of the building, there is a hole with an invisible wall blocking you from coming in. Inside the hole is what is maybe the manager of the burger place. It is an NPC that does not move. It is not confirmed that this is the manager, though.
This is also often referred to as the Ratman or the Stalker.