Cain and His Disease

Cain has a disease known as toxic multinodular goitre, or Plummer's Disease. His symptoms are mainly tachycardia, weight loss, heat intolerance, irritability, and cases of hyperkinesis.

Tachycardia is the worst of them, as it has lead to ischaemic heart disease. Which, in turn, has worsened. A contributor to it is his smoking. So, in particularly bad situations, Cain's heart doesn't fare too well.

I'm a jerk to this kid.