Blood Limitations 2

Cuban on the other hand, Chuckled lowly, "I can see that it has finally kicked in. The immense fatigue must be hard to understand, but don't worry, as a blood demon, I am most familiar with your plight. Allow me to explain...

You see, the secret is blood. It has always been blood. 

From the moment you entered the wandering city, you entered a private sub plane, where the most valuable thing here is blood. 

But blood works with authority, meaning that one can only give or use what one has authority over. 

Also, its quantity or quality has to be proportional to its exchange. 

At the end of the day, both of you, although strong, are only human at your core. 

This is something you cannot fight against.

Are you aware that only about ten percent of a fully grown adult's body weight forms their blood? 

This means that each human works with only 1.2 to 1.5 gallons of blood.