Process cartridge and image forming apparatus including the same

A process cartridge comprising:

• a first cartridge comprising:
• a developer container configured to contain developer and including an output port wall where an opening is open, the developer being to be conveyed from the developer container through the opening;
• and
• a second cartridge comprising:
• a developing roller configured to develop a developer image on a photosensitive drum and including a first shaft;
• a supply roller configured to supply the developer to the developer roller and including a second shaft;
• a case having an input port through which the developer is to be supplied from the opening of the first cartridge, the case being configured to rotatably support the first shaft of the developing roller and the second shaft of the supply roller;
• a protrusion protruding from the case;
• a frame on which the first cartridge is configured to be mounted, the frame comprising:
• a side frame configured to rotatably support the photosensitive drum and having a first hole in which the protrusion is slidably inserted;
• and
• a bottom frame configured to support the first cartridge;
• and
• a guide extending horizontally and configured to guide the first cartridge between a predetermined position where a portion of the first cartridge is out of the bottom frame, and a mounted position where the bottom frame supports the first cartridge thereon.