Kamalnayan Bajaj, or Kam, was a friend of the Doctor. He lived in Calcutta, India with his family and owned a restaurant.
At one point before 1937, the Doctor helped him with an infestation of Jakra worms. In return, he allowed the Doctor to eat free at his restaurant.
In 1941, the Doctor visited Kam for Navratri, bringing his own fireworks.
In 1947, the conflicts in India became too violent and Kam and his family fled Calcutta. His restaurant was burnt down. The Tenth Doctor brought Donna Noble to his restaurant for Indian food, but missed the year, arriving after he had left Calcutta. (PROSE: Ghosts of India)