These red bugs looked just like the red blood cells within a biological organism. Those without powerful Spiritual Sense simply could not "see" them.
What was strange was that these red bugs had always been lurking within your body, highly sensitive to Mental Power, Spiritual Sense, and even Immortal Sense.
The moment the "host's" Mental Power or Spiritual Sense fluctuated, they could sense it immediately. And they would disguise themselves right away.
This type of Alien Insects, called Essence Bugs, was a kind of extremely mysterious insect mentioned in legends.
They most liked to parasitize within creatures with strong inner vital energy and spirit, thereby stealing the host's essence and life force for their own use.
