Provided is a damper configured so that a compact pedal unit can be obtained using the damper and so that the damper can be easily retrofitted to a pedal unit. A damper (1) comprises elements such as: a pair of cams (slide cam (4) and stationary cam (5)) which rotate relative to each other about the axis (O1) to cause the sloped cam surfaces (4132, 5211) thereof to make sliding contact with each other; a coiled spring (3) which presses the sloped cam surface (4132) of the slide cam (4) against the sloped cam surface (5211) of the stationary cam (5); a case (2); and a resin roller (8) which is fitted in a rotatable manner on the shaft (7A). The rotational motion of the slide cam (4) about the axis (O1) is restrained by the case (2), and as a result, the slide cam (4) rotates about the axis (O1) relative to the stationary cam (5) in association with the rotation of the case (2) about O1.