A period of time lasting a few days, normally spanning over a weekend, when two individuals (Sparrow and Wad) are reunited. Wad and Sparrow sequester themselves in Wad's room when Wad is not in class or studio. When Wad does go to class or studio, Sparrow follows faithfully. Carnivale also refers to Sparrow's presence in class or studio.
Sparrow is in Studio, so I say to Marcus, "Hey, it's Carnivale!"