1. A computer readable medium for providing a virtual agent, wherein the medium stores a first agent parameter controlling a first agent kept by a first person a first computer operated by the first person; stores a first image data of the first agent on the first computer; stores a second image data of a second agent being kept by second person on the first computer; displays the first agent on a first screen connected to the first computer based on the first image data and the first agent parameter; and wherein the first agent parameter is sent to the first computer through a communication network.