whereas Ki indicates one or more of anime fan / Aikido practitioner / practitioner of Japanese spirituality. (These are more probabilities than hard categories; Reiki is a good counterexample.)

Chinese spirituality/meditation practices/internal martial arts like T'ai chi ch'uan and Qigong also use the concept of qi in that sense. In fact, all Japanese martial arts and spirituality/meditation practices derive from Chinese ones.

Qi, ki, prana, etc. are pretty much the same concept, also similar to traditional Western concepts such as pneuma (spirit), psyche/anima (soul), vis vitalis, and so on. People form all cultures noticed early on significant qualitative differences between living things, specifically animals (literally, "things with a soul") and non-living things, but without a scientific body of knowledge they couldn't precisely define what life was in a reductionist way, so they resorted to broad and vague notions of "life force", typically associated with breathing.

Today we have more reductionist definitions of life, typically involving reproduction and homeostasis while in thermodynamic disequilibrium, but we still struggle with a reductionist definition of consciousness.