a seat main body;

at least one sensor provided in the seat main body;

a control device configured to process a signal from the sensor;

a first user interface and a second user interface each configured to communicate with the control device and to notify information based on a signal from the control device; and

a camera configured to capture an image of a seated person who is seated on the seat main body;

wherein the control device includes an application processing unit configured to execute an application based on a signal from the sensor and a viewing image creation unit,

wherein the application processing unit generates an application screen, causes the second user interface to display the application screen, executes application processes based on signals from the sensor, and changes the application screen displayed on the second user interface,

wherein the viewing image creation unit creates a viewing image based on both image information from the camera and the application screen,

wherein the control device transmits the viewing image to the first user interface, and

wherein the first user interface displays the viewing image including both the image of the seated person and the application screen,

wherein the sensor detects a motion of a body of a user seated on the seat main body, and

wherein the application processing unit moves a character in the application screen based on the signal of the sensor.