Contents receiving system and client

A contents receiving system comprising:

• a content receiver;
• and
• a portable terminal storing ID information with which its user can be distinguished from other users of other portable terminals,
• the content receiver including:
• a receiving unit capable of receiving content and subsidiary content from at least one of a broadcast wave and a network;
• an output unit capable of outputting, as audio video content, a video and/or audio of the content received by the receiving unit;
• a transmission unit capable of transmitting the subsidiary content to the portable terminal, the transmission unit enabling information on a payment transaction corresponding to an ID information of the portable terminal to be transmitted to the portable terminal individually,
• the portable terminal including:
• a second transmission unit capable of receiving the subsidiary content and the information on the payment transaction transmitted from the transmission unit of the content receiver;
• and
• a processing unit for performing a processing regarding the payment transaction of the content by use of the information on the payment transaction received at the second transmission unit.