[Answer]-Django admin form – ManyToMany behavior with ForeignKey

Yes it is feasible but only through pop-ups (with the already django build in admin), if you want to edit the remote object (C) from A directly in the form then you need to make changes in your admin, such as creating a special view, assigning the appropriate queries etc.
Also note that you will need to register all 3 models with the admin, otherwise you will be able to access (popup) only the models registered.