A developer cartridge for use in an image forming apparatus may include a casing extending in a longitudinal direction and having an opening communicating with the image forming apparatus. The cartridge may further include a grip that, in some arrangements, is disposed at an opposite end relative to the opening in the longitudinal direction. Additionally or alternatively, the developer cartridge may include an agitator comprising a shaft and a gear. The gear may, in some examples, be provided at the same end as the grip and be fixed to the shaft. A distance between the opening and the gear may be shorter than a distance between the opening and the grip.