Disclosed is a pullback system, which has a simplified and miniaturized structure and an advanced function. The pullback system includes a central unit, which includes a rotation transducer part that rotates, and a stretchable part that is connected to a side of the rotation transducer part to rotate together with the rotation transducer part and that has a stretchable property, and a first unit rotatably coupled to a portion of the central unit. As the first unit moves in a first direction oriented from the rotation transducer part to the stretchable part or in a second direction opposite to the first direction, the stretchable part contacts or stretches.