Breathe in, breathe out

Drawn by Stupiee in Sketchport

"The desire to breathe is among our most primitive urges. We're designed to draw air into our lungs, to exchange fresh oxygen for the waste gas of carbon dioxide. Our lives depend upon this perpetual to and fro of gases ..."

https://delanceyplace.com/view-archives.php?p=3530&utm

"This is the most delicate interface in your body. Nowhere else is the point of contact between your body and the material from the outside world more insubstantial or delicate. That is why it is buried deep in your chest and protected with a formidable cage of ribs."