A damper for damping a movable member along an axis, the damper comprising: a housing in a cylindrical shape, having an inner wall configured to surround the movable member about the axis, the inner wall being provided with a cam groove in a helical form winding about the axis; a friction generating section placed in the housing and configured to move with the movable member along the axis; and an elastic member placed in the housing, being to urge the friction generating section by an elastic force depending on an amount of displacement of the movable member, in a direction of pressing the friction generating section against the movable member; and the friction generating section comprising: a first friction member configured to be displaced toward the elastic member in response to a force from the movable member; a second friction member configured to be displaced toward the elastic member to compress the elastic member; and a third friction member having an outer peripheral surface provided with a guide protrusion inserted in the cam groove, the third friction member configured to move with the first and second friction members along the axis while being pressed between the first and second friction members, the third friction member in motion configured to be rotated about the axis by the guide protrusion guided through the cam groove; wherein the inner wall of the housing has a guide groove along the axis, at least one friction member of the first and second friction members has a guide protrusion (53, 73) inserted in the guide groove so as to be guided through the guide groove while preventing a rotation of the first and second friction members relative to the housing, and the third friction member is provided with a through hole at a position which the axis passes through, characterized in that one friction member of the first and second friction members has a boss part inserted in the through hole of the third friction member, the other one of the first and second friction members is provided with a boss insertion hole, the boss part is inserted into the boss insertion hole through the through hole of the third friction member, and an outer peripheral surface of the boss part and an inner peripheral surface of the boss insertion hole include opposing surfaces configured to contact with each other to prevent a relative rotation between the first and second friction members. a housing in a cylindrical shape, having an inner wall configured to surround the movable member about the axis, the inner wall being provided with a cam groove in a helical form winding about the axis; a friction generating section placed in the housing and configured to move with the movable member along the axis; and an elastic member placed in the housing, being to urge the friction generating section by an elastic force depending on an amount of displacement of the movable member, in a direction of pressing the friction generating section against the movable member; and the friction generating section comprising: a first friction member configured to be displaced toward the elastic member in response to a force from the movable member; a second friction member configured to be displaced toward the elastic member to compress the elastic member; and a third friction member having an outer peripheral surface provided with a guide protrusion inserted in the cam groove, the third friction member configured to move with the first and second friction members along the axis while being pressed between the first and second friction members, the third friction member in motion configured to be rotated about the axis by the guide protrusion guided through the cam groove; a first friction member configured to be displaced toward the elastic member in response to a force from the movable member; a second friction member configured to be displaced toward the elastic member to compress the elastic member; and a third friction member having an outer peripheral surface provided with a guide protrusion inserted in the cam groove, the third friction member configured to move with the first and second friction members along the axis while being pressed between the first and second friction members, the third friction member in motion configured to be rotated about the axis by the guide protrusion guided through the cam groove; wherein the inner wall of the housing has a guide groove along the axis, at least one friction member of the first and second friction members has a guide protrusion (53, 73) inserted in the guide groove so as to be guided through the guide groove while preventing a rotation of the first and second friction members relative to the housing, and the third friction member is provided with a through hole at a position which the axis passes through, characterized in that one friction member of the first and second friction members has a boss part inserted in the through hole of the third friction member, the other one of the first and second friction members is provided with a boss insertion hole, the boss part is inserted into the boss insertion hole through the through hole of the third friction member, and an outer peripheral surface of the boss part and an inner peripheral surface of the boss insertion hole include opposing surfaces configured to contact with each other to prevent a relative rotation between the first and second friction members.