Nobody asked but …
In any dimension (and there are uncountable instances of them), there is always a clear separateness of any two entities. There is a marker where I stop and you begin. The marker is, in most practical senses, easy to observe. If you and I are standing in a room, within physical reach of one another, it is the place where we may touch, with a handshake, for instance. If we are farther apart, then about half the distance belongs psychologically to me, while the other half belongs to you. Now, other things equal, we are in the land of voluntaryism. And in this case, based on the facts, other things are equal either in importance or in irrelevance. There are no actual, natural facts that cede more of this space to you than to me. If we can keep this balance, we are in a voluntary association. If I cross the space, uninvited by you, to strike you with a truncheon because I am a minion of an oligarchy which regards you as an undesireable, then I am not a voluntaryist but you still are a voluntaryist. Voluntarily, you may do whatever to remove my degraded existence from your space … or you may do whatever to accomodate me into your space.