In the near future, severe environmental pollution has led to the extinction of numerous livestock species, plunging humanity into a food crisis. Humanity's only salvation lies in the mutants created by pollution and genetic modification. Some humans began producing milk like livestock, prompting the government to establish a system called the ‘Human Dairy Farm’...

“But... why did I end up like this?”

Eui-Je, who reported the school's obnoxious popular guy, Cassie, as a human cow, somehow finds himself entering that very ranch.

(Source: MrBlue, translated)

Note: Includes one extra chapter.