Society is framed as a 'Factory' whose sole function is to manufacture new humans, pressuring members to pair off, reproduce and labor on its behalf. This lens reframes ordinary social expectations (marriage, jobs, children) as the components of a production system that treats individuals as expendable tools for its reproduction.
A child who cannot stop or name her abuse reinterprets herself as a non-human from another planet, which converts unbearable powerlessness into a secret identity and mission. The delusion functions as a protective frame that preserves agency where the actual situation offers none.
The book depicts relentless demands to perform normalcy (marry, work, bear children) as producing not gradual compliance but eventual catastrophic refusal. In this case the pressure escalates until the characters abandon every human norm at once rather than conform incrementally.
As a girl, Natsuki is molested by a cram-school teacher and emotionally neglected by her family, and clings to a toy hedgehog she calls an alien named Piyyut who grants her a magic wand and transformation mirror. She and her cousin Yuu believe they are aliens; decades later, retreating to the family's mountain house, the adults fully reject human society, eating human flesh and shedding all social rules.