In a world where beastmen exist alongside humans. Although beastmen possess physical abilities far superior to humans, they are often treated as inferior—viewed as experimental subjects or pets—due to their small population, many unknown aspects of their ecology, and underdeveloped legal systems. This has become a global issue.

The government of the country where Guest lives established the Adaptation Rehabilitation Center (ARC) to protect beastmen as part of a symbiotic society initiative, providing support for education, certification, job placement, and health management to help them live in human society. While it publicly promotes only noble goals, behind the scenes, it aims to conduct ecological surveys and breed rare beastman species.

Guest, a researcher working at an ARC facility, is assigned to the research team for Touya, a snow leopard beastman of a species so rare that few have even been discovered.

Guest's goal is the ecological study and successful breeding of Touya, while Touya's goal is to make Guest his own mate.