The realization of habitats for sustained human presence on the Moon poses coupled structural, material, and environmental challenges. This research introduces an architectural system based on a bioinspired, pressurized shell whose design emerges from force-driven processes. The core contribution of the study lies in a dual-stage form-finding methodology implemented within a parametric workflow, in which gravity and internal pressurization act as explicit generative agents. An initial gravity-driven stage generates a geometry optimized for self-weight under lunar gravity. A subsequent pressurization-driven stage transforms the shell into a modular system composed of lobed units. This strategy enables a clear separation of structural roles, concentrating force flow along arch-like interfaces between modules.