Multi-refill writing instrument

A multi-refill writing instrument comprising:

• a barrel;
• a plurality of writing bodies accommodated in the barrel so as to be movable in a axial direction of the barrel;
• a plurality of elastic bodies urging the writing bodes backward;
• a plurality of operating bodies connected to rear ends of the corresponding writing bodies;
• and
• a plurality of window holes formed in a side wall of the barrel so as to extend in the axial direction,
• wherein the operating bodies protrude from the barrel to an outside through the window holes in the radial direction,
• one of the operating bodies slides forward along the window hole so that a nib of the writing body connected to the one operating body protrudes from the barrel through a front hole, and simultaneously, a nib of another writing body in a protruding state is retracted into the barrel, and
• the writing bodies and the operating bodes are adapted to be pulled out from the barrel and to be inserted into the barrel.