you got a laser pointer? go find the longest straight line of sight you can in your home and aim at something small across that distance
hold it
hold it
yeah. now imagine because 40k lore is full of space marine wank you have a second heart, somehow your ribcage has fused around your lungs (how does this work?), and because you're technically still human your circulatory system still functions
you breathe. your heart beats. blood and other fluids are constantly moving inside your body










