Aperture Science Weighted Storage Cube

The Weighted Companion Cube was an inanimate but undeniably affectionate object which Chell used during the events of Portal.

Description and Role
The Companion Cube was different to the standard Weighted Aperture Science Cube in that it was decorated with a pink heart on each of its sides. It was delivered to Chell from a ceiling socket by GLaDOS at the beginning of Level 17, and was critical to completing the level successfully. GLaDOS warned Chell that the Companion Cube could not talk, and that even if it did talk she was advised to ignore any suggestions it cared to make.

Despite GLaDOS's insistence upon (and the reality of) the inanimacy of the Weighted Companion Cube, she forced Chell to destroy it in an Aperture Science Incinerator Unit at the end of Level 17. "Well done," she said after Chell had accomplished this, "You chose to destroy your companion faster than any other previous test subject." She went on to accuse Chell of murdering the Cube at the end of Portal.

The Cube can also be seen on the main menu after the successful completion of the game.