an external input unit configured to input a signal of contents including an image from said second wearable display, said {HEAD ~ second wearable display} being of {TAIL ~ a second user}, 
an external input unit configured to input a signal of contents including an image from said second wearable display , said { HEAD ~ second wearable display } being of { TAIL ~ a second user } ,
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH