Character: weighted companion cube (portal)

"The Weighted Companion Cube will never threaten to stab you and, in fact, cannot speak. In the event that the Companion Cube does speak, the Enrichment Center urges you to disregard its advice."
GLaDOS

The Weighted Companion Cube is an inanimate object companion given to Chell in one segment of the game Portal. This 'character' is no different from any other boxes found in the game, other than that it has a heart drawn on its sides.