A liquid consumption system comprising: a cartridge; and a liquid consumption apparatus, the cartridge comprising: a first storage chamber (32, 33) storing a liquid; a first air communication portion allowing the first storage chamber (32, 33) to communicate with an atmosphere; and a supply portion configured to supply the liquid stored in the first storage chamber (32, 33), the liquid consumption apparatus being configured to consume the liquid supplied from the supply portion of the cartridge, the liquid consumption apparatus comprising: a cartridge attachment section; and a consuming section, the cartridge attachment section comprising: a connecting portion configured to be connected with and disconnected from the supply portion; and a tank, the tank comprising: a liquid flow-in port allowing the liquid, which has been supplied from the first storage chamber (32, 33) through the supply portion and the connecting portion connected with the supply portion, to pass though the liquid flow-in port; a second storage chamber (121,122, 123) configured to store the liquid that has flown through the liquid flow-in port; a liquid flow-out port disposed at a position below the liquid flow-in port and configured to allow the liquid stored in the second storage chamber (121, 122, 123) to flow out of the second storage chamber (121, 122, 123); and a second air communication portion allowing the second storage chamber (121, 122, 123) to communicate with the atmosphere, the consuming section being configured to consume the liquid flown from the second storage chamber (121, 122, 123) through the liquid flow-out port; the cartridge further comprising a wall defining a first base part and a first protruding part, the first storage chamber (32, 33) extending over insides of both of the first base part and the first protruding part, the tank further comprising a wall (151, 152, 153, 154, 144, 145) defining a second base part and a second protruding part, the second storage chamber (121, 122, 123) extending over insides of both of the second base part and the second protruding part, the supply portion and the connecting portion being connected together in a case where the cartridge is inserted into the cartridge attachment section in an inserting direction that is parallel to the horizontal direction, the supply portion and the connecting portion being separated from each other in a case where the cartridge is detached from the cartridge attachment section in a detaching direction that is opposite to the inserting direction, in a used posture of the liquid consumption system, the first protruding part protruding in the inserting direction from an upper portion of the first base part that is defined in a vertical direction, and the second protruding part protruding in the detaching direction from a lower portion of the second base part that is defined in the vertical direction, in a state where the supply portion is connected to the connecting portion, the first base part and the first protruding part having the following positional relationship with the second base part and the second protruding part: as viewed in the inserting direction, the first base part is overlapped with both of the second base part and the second protruding part; as viewed in the vertical direction, the first base part is not overlapped with the second base part, and is not overlapped with the second protruding part; as viewed in the inserting direction, the first protruding part is overlapped with the second base part, but is not overlapped with the second protruding part; and as viewed in the vertical direction, the first protruding part is overlapped with the second protruding part, but is not overlapped with the second base part. a first storage chamber (32, 33) storing a liquid; a first air communication portion allowing the first storage chamber (32, 33) to communicate with an atmosphere; and a supply portion configured to supply the liquid stored in the first storage chamber (32, 33), a cartridge attachment section; and a consuming section, a connecting portion configured to be connected with and disconnected from the supply portion; and a tank, a liquid flow-in port allowing the liquid, which has been supplied from the first storage chamber (32, 33) through the supply portion and the connecting portion connected with the supply portion, to pass though the liquid flow-in port; a second storage chamber (121,122, 123) configured to store the liquid that has flown through the liquid flow-in port; a liquid flow-out port disposed at a position below the liquid flow-in port and configured to allow the liquid stored in the second storage chamber (121, 122, 123) to flow out of the second storage chamber (121, 122, 123); and a second air communication portion allowing the second storage chamber (121, 122, 123) to communicate with the atmosphere, as viewed in the inserting direction, the first base part is overlapped with both of the second base part and the second protruding part; as viewed in the vertical direction, the first base part is not overlapped with the second base part, and is not overlapped with the second protruding part; as viewed in the inserting direction, the first protruding part is overlapped with the second base part, but is not overlapped with the second protruding part; and as viewed in the vertical direction, the first protruding part is overlapped with the second protruding part, but is not overlapped with the second base part.