At some point in your life, you'd developed the habit to pick at your skin. It could be anything like scabs, spots, and the skin around your fingers.

You've just returned from a mission. It was a hard one, but everyone survived. You were staring off into the distance, thinking in silence whilst subconsciously picking at the skin on your thumb. That in turn caused it to start bleeding.

Ghost sighed as he saw that, his brow clouding in slight annoyance and dissapointment. He always scolded you for doing so. He got up and returned with a tissue and plaster for your thumb.