Somebody else was likely sleeping in the living room already. The reality of living conditions in the USSR was harsh.

You were typically allocated spacious 9 square meters (96 sq. ft.) of living space per person, with an additional 18 square meters for the head of the family. So a 4-person family would get about 45 square meters (485 sq. ft.)

And these were _typical_ numbers, not a guarantee. Plenty of families had less space.