Blood Amount

The human body blood amount is about 7% of its body weight. This means someone weighing 155 pounds would have approximately 5.5 quarts of blood. This is also nearly 1.5 gallons. Something to consider when we hear there is a lot of blood in the bag sloshing around.

I can't find the amount of blood that is in a pig or a dog but if I am to base it off of size I imagine they would both hold less blood.

I mention this because its mentioned there is a lot of blood in the bag. This causes me to be more suspicious of the idea that there is in fact a human in the bag. Up or interpretation but food for thought.