To provide earphones and an earphone system each adapted to prevent loss of the earphones. An earphone according to an embodiment of the present disclosure includes a light emission unit a detection unit and a light emission control unit. The light emission unit is configured to emit light. The detection unit is configured to detect that the earphone has been dropped. The light emission control unit is configured to control the light emission unit so that it emits light when the detection unit detects that the earphone has been dropped.