Kumar, a trader’s son, born in Calcutta, Bengal, was the eldest of seven children. After local schooling at Mitra Institute, Kolkata, he went on to Bangabasi College. The family had a large Departmental Store at Shyambazar and the family had their ancestral house nearby. Kumar lived with his parents before moving separately to Taltola, in the early 1930s. He did odd jobs and tried his hand at writing, which in his own words, he failed miserably. Thereafter, he started collecting rare books, which became his passion. This he turned into a business, at which he was neither a success nor could he make it pay for his living. This did not deter him and he continued with his passion. In 1900 he invited his parents to come and live with him, as his father had a misfortune in business. His parents arranged for his marriage to Karuna, who was a teacher in a school, in a sleepy railway hamlet, called Adra, which is in the border of Bengal and Bihar. Their thinking was that they would make a good pair as books and teaching go together. He continued working on his collection, but side-by-side gave support to a lot many fledging artists and writers in those days.