Sanguine
1) Having a ruddy (reddish) complexion.
2) Cheerful, hopeful, confident, and optimistic; impulsive.</P> The word 'sanguine' from the Latin 'sanguineus' for 'blood' has long been used in English for things relating to the blood.
A person who is ruddy in complexion is sanguine.
His (or her) ruddy countenance was once thought to be due to their having a predominance of one of the four humors -- blood.