From the introduction:
In Honor of Doug Winger: 1953-2015
Welcome to planet Winger. A place much like Earth, and yet very different. All thanks to the discovery of Winger Energy, by Doctor Doug Winger. This energy is produced by humans but can only be extracted through sexual fluids (milk, vaginal secretions, but mostly semen). After this discovery, mankind began working on cross genetics fusion for more sources of Winger Energy, resulting in the creation of Anthros/Furries.