Ki is the Japanese term for Life energy.
There are seven energies on the physical plane with ReiKi being the highest of the seven energies which in turn connects with divine energy otherwise known as ShinKi.
Kekki - the KI of blood - provides fundamental strength. It is the most powerful and most basic of the seven energies, and the least structured.*(*Reiki: the true story by Don Beckett)It is a known fact that the strength of a person's blood is what gives them the foundation to approach their life with a certain amount of vigor and consistency. If the blood is poor the person can suffer from fatigue and all sorts of ailments such as iron anemia. If there is not enough oxygen in the blood or not enough red blood cell production the foundation of a person's energy is affected.
Good strong Kekki , the ki of blood is very important. Kekki is indeed the essence of who we are physically speaking.
Keep your kekki strong and flowing.