Image forming apparatus and image forming unit

An image forming unit comprising:

• an image holder that is provided to be rotatable and is attachable to and detachable from a main body of an image forming apparatus;
• and
• a charging member that includes a charging member main body that has an outer circumferential surface and that is provided to be rotatable and a cover member that covers an outer circumferential surface of the charging member main body which is a separate member from the charging member main body, in which an outer circumferential surface of the cover member is disposed to be in contact with the image holder, and that charges the image holder, wherein the image holder and the charging member main body are the only rotating devices which are used to rotate the cover member around the charging member main body,
• wherein a circumferential speed of one member of the rotating image holder and the rotating charging member main body is greater than a circumferential speed of the other member, and
• wherein the cover member moves to follow a movement of the one member at a contact portion where the cover member and the image holder come into contact with each other, and a portion of the cover member that is positioned on an upstream side of the contact portion is drawn toward a downstream side of the contact portion so that the cover member becomes deformed to have an asymmetric shape between the upstream side of the contact portion and the downstream side of the contact portion and so that the cover member contacts the charging member main body at location other than the contact portion on an upstream side of the charging member main body.