Vtuber Character Rigger is a face rigging add-on that sets up 3D model faces for keyframed animation. It utilizes existing ARKit blendshapes, also known as Perfect Sync, to drive the facial movements. The tool simplifies the rigging process by eliminating the need for weight painting, allowing users to bind the mesh to the face armature with a single click. Additionally, it includes functionality to merge the newly created face armature with an existing body armature.