A tether (60) has a pair of guide plates (64). The pair of guide plates (64) has two facing sides (64a), the distance between which increases toward the front end of the tether. The tether (60) may have an elastic section (66). The pair of guide plates (64) may have protrusions (64d) protruding toward an anchor (62). A tether intermediate section (60a) may be bent, and the tether (60) may be extended in length. The tether (60) may have second and third guide plates (76, 78). When a pillar garnish (80) moves in the direction away from a pillar (90), the two sides (64a) of the guide plates make contact with an edge of a tether insertion hole (86) to prevent the tether (60) from rotating about a clip center axis (10a) and to prevent the anchor (62) from coming out through the tether insertion hole. The elastic section (66) and the protrusions (64d) prevent the rotation of the tether (60) when a tether housing section bottom wall (84) comes between the guide plates (64) and the anchor (62). The second and third guide plates (76, 78) also prevent the rotation of the tether (60).