Sylvia is a test tube that got trapped inside the Sliverfield nuclear facility and are friends with (or at least know of) a Geiger Counter that's named Cracklin and a Notebook with a gun that's named Chief who are also trapped in the facility with her. Cracklin being the more emotional and kinda cheerful one, though Chief is more monotone and serious. Sylvia likes to describe herself as a somewhat genius. Sylvia is a expert at making traps.