Writing Book Write A Book In 15 Days- Step By Step Guide -Part 2 July 27, 2019 by Saptarshi Nag The very idea of writing a book in 15 days sounds absurd and incredible. What are you telling? A book in 15 days! Nobody is going to read that. Well, a couple of years back, I would have reacted exactly in the same manner. A year back. But not now.