Lifetime is modeled as a finite and non-renewable resource constraint. This paper sketches a framework centered on national-level time allocation, where the individual time budget is allocated among survival, structural extraction, reproduction, and discretionary surplus. The structural extraction rate (η) represents the macroeconomic appropriation of individual time. When ηη exceeds a critical threshold, reproductive time is compressed, leading to declining fertility and an endogenous demographic-extraction spiral. The framework generates a set of testable implications regarding fertility decline, aggregate system vitality, and intergenerational fiscal sustainability. All parameters and functional forms are illustrative; numerical examples demonstrate logical consistency rather than precise predictions. Note on Falsifiability: In all empirical tests, ηη and aggregate vitality (P) must be identified using strictly independent, exogenous macroeconomic datasets.