 House reluctantly takes on the case of Kalvin, a man who is HIV Positive. The HIV medicine he has been taking has greatly improved his immune system but he continues to get sicker. When Kalvin starts coughing up blood, he accidentally coughs some on Cameron and there s a chance she may contract the disease. In the wake of this, he tries to convince Cameron to be a little more free-spirited as the start to a happier life. Meanwhile, in a bid to improve his relationship with Stacy, House makes it his mission to capture a rat that is running around her house.