Imaging unit, developing unit, photosensitive unit, and image forming apparatus

Provided is an imaging unit, including: a developing unit having a developing roller and a first abutting member; a photosensitive unit having a photosensitive drum and a second abutting member, a gap between the photosensitive drum and the developing roller being set constant by bringing the first abutting member into abutting contact with the second abutting member; a cleaner configured to be disposed in a space between the first and the second abutting members in a separate state where the first abutting member is spaced away from the second abutting member; and a displacement unit configured to displace the cleaner from the space as the first abutting member is brought close to the second abutting member. In the displacement, the displacement unit causes the cleaner to slide on an abutting surface of at least one of the first and the second abutting members.