An apparatus, system, and method of managing candidate counterpart terminal information, each of which determines, in response to a request for adding a candidate counterpart terminal to a candidate list of a request sender terminal, whether attribute information stored in association with the request sender terminal matches attribute information stored in association with the candidate counterpart terminal to be added, and stores counterpart terminal identification information that identifies the candidate counterpart terminal in association with terminal identification information of the request sender terminal to update the candidate list of the specific request sender terminal when a determination result indicates that the attribute information match.