When someone stays up until the early ass hours of the morning. They're running off of coffee blood, thus using the caffeine to keep themselves running at such late hours.

It is only possible to obtain coffee blood once you have stayed up passed three in the morning for four consecutive days.

The first discovery of Coffee Blood (or Caffeinated Blood) was back in the early 20s when people were often found staying up late without necessary reason.

Throughout the following decades, the infected race (Caffeinate Coagulus) was recorded to consist mostly of teenagers and young adults.

Now, in more recent studies, it still seems that the age group has not changed. However, there are some outliers in younger or older age groups that have relevant reasons for staying up after such a late hour of the morning.
Doctor: "It seems that our patients have Coffee Blood."

Assistant: "The following patients: Miranda, Martha, Kristen, Ry, Becca, Cidra, James, Alycia, Brian, Shannon, Andrew, and Sarah all seem to be having symptoms, sir."

Doctor: "Dammit! Why can't we find a cure for this?!"
by BeMyCaptivation July 17, 2010
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