Updated 3/12/2022. Completely overhauled. Able to be implemented in VR Chat and standardUnity 3d character rigs. https://lb3d.co/professional-parasite-unity-3d-avatar-documentation/
This is now available on the Unity 3d market place.
Based on common social leeches, otherwise called "Professional Parasites".
Original file is a .blend Blender project. If you download this, it is expected that you should know what you are doing.
Note: This has been updated to include the downloadable source file.