# File lib/mongoid/relations/referenced/many_to_many.rb, line 155
        def nullify
          unless metadata.forced_nil_inverse?
            criteria.pull(metadata.inverse_foreign_key, base.id)
          end
          if persistable?
            base.set(
              metadata.foreign_key,
              base.send(metadata.foreign_key).clear
            )
          end
          target.clear do |doc|
            unbind_one(doc)
          end
        end