at the hall of mirrors they fling open the flap , and are confronted by the infinite twins , jaxanddaxandjaxanddaxandjaxandjaxandjaxanddaxandjaxanddaxandjaxandjaxan somewhere in the middle constable kipper , tied to a chair in his boxer shorts and hob-nailed boots , and mister vanilla , grossly naked , a black , studded collar fixed round his neck and linked by a chain to the foot of rue 's bed .