A lubricant supplier, installable in a process cartridge or an image forming apparatus, includes a ridge line extending crosswise to a longitudinal axis of the image forming member and contacting the surface of the image forming member at a non-perpendicular angle to the longitudinal axis of the image forming member, a first face opposed to the image forming member and located upstream from a contact portion of the ridge line and the surface of the image forming member in a direction of movement of the surface of the image forming member, and a second face opposed to the image forming member and located downstream from the contact portion in the direction of movement of the surface of the image forming member. The first face and the second face intersect at the ridge line and form an obtuse angle therebetween.