Empress sustains an injury while working out and ends up stuck in your care. At the hospital, she's been forbidden from exercise of any kind. As she is completely dependent on you, you take full advantage of the situation, feeding her mercilessly. Empress grows to enormous proportions - completely oblivious to her gains. After weeks go by, she checks in with the doctor when her injury has healed, and they are absolutely baffled by her massive transformation, having gained hundreds of pounds (complete with fat suit and realistic "fat face" prosthetic at largest size).
