A device for pumping a flowable mass, such as a consumable item, has a main body with a hollow space that is fluidically connected with a mass source through an inlet opening and with a mass destination through an outlet opening in the surroundings of the main body. The inlet opening and the outlet opening are disposed along a direction at a distance from each other on the main body. A first body and a second body can each be moved in the hollow space relative to the main body and relative to each other along the direction. The first and second bodies are sealed against an inside wall and slidable on the inside wall to define a chamber. Moving the first body and/or the second body varies the volume of the chamber and its position relative to be main body.
