Chi is the life force and energy of all living Fae and humans that Succubi must feed from to survive and to heal.
In traditional Chinese culture, qi is an active principle forming part of any living thing. Qi is frequently translated as "natural energy", "life force", or "energy flow". References to concepts analogous to the qi taken to be the life-process or flow of energy that sustains living beings are found in many belief systems, especially in Asia.
"Life force" is the concept that a fundamental energy animates all living organisms. Many cultures and religions, past and present, believe in its existence: