I have a question here from Lucas Skyminded, who asks:

How much time do Low, Brink and Maggie stay on Cocytus? You know, since they arrive to they departure, when the cocytans helps them to get back Earth..

I was thinking a matter of days, but I'm not sure. Does anyone, especially those who've read the book, know anymore than this?

In the book they're there for about two days. Night falls and Maggie and Boston watch over(And presumably sleep some as well, I would think they'd be too tired to stay up all night) Ludger after they cut off his hand. The next morning they eat some berries and drink water. It's still daytime when they leave Cocytus, that would be two days and one night. They're just there for a day in the game since it never becomes night.