Who is Nawab Sahib of Baitar from A Suitable Boy: A Novel and what is their importance?

The Nawab Sahib is the father of Firoz Khan. Although he is Muslim, he and Mahesh Kapoor are good friends until the unfortunate accident involving Firoz and Maan Kapoor. The Nawab Sahib is in danger of losing a great deal of his family land through the Zamindari Abolition Bill.