Yes, "Kessa" DOES exist, and it IS out there! It just takes some looking for. I was lucky enough to find a copy through my local library's Inter-Library Loan System. If your library has something similar, I suggest trying to find it through that.
As you probably know, "Kessa" is the sequel to "The Best Little Girl in the World", Stephen Leverkron's (in)famous story about Francesca Louise Dietrich (aka Kessa), a girl who is hospitalized for severe anorexia. BLGITW ends with Kessa's impending release from the hospital. As anyone with an eating disorders knows, this is often the first step down the long and difficult road to recovery. "Kessa" acknowledges this, as it depicts the troubled girl's struggle to get her life back.
The best thing this book has going for it is the development of the Kessa's character. Unlike BLGITW, where Kessa is little more than anorexia incarnate, we get to see aspects of her personality other than the eating disorder. We see all her hopes, her passions, her fears, and her opinions that DONT revolve around food as well as some of her interactions with others; in short, she has depth. I found myself relating very easily to her on a very intimate & human level.
Granted, the book has it's flaws. For example, the storyline will often randomly flash back to recount past events, with awkard and often confusing results. There are lots of other characters, very few of which are well-developed, if at all. Levenkron makes a few feeble attempts to inject some social commentary outside his area of expertise (namely racism & segregation) that fail to do justice & perhaps even minimize these important subjects. There is also too much dialouge between Kessa & her therapist. While some of this is interesting, it goes a bit too far; waxes a bit too theoretical to hold my interest. Perhaps worst of all, there is a tragic event injected into the plot that I don't think was dealt with well at all. (I won't say any more to avoid spoiling the story, though). Also, let's face it: this is not noble-prize winning literature; hence it is no longer in publication. Still, the book is an engaging, even adicting read -- I literally couldn't put it down, and finished all 247 pages in a couple hours.
Well, good luck finding this book -- I think you'll find it's well worth the time & effort it takes to find it*
*but not worth the 90 bucks or whatever they're asking for it here -- keep looking; go to a rare or used book store, I promise you, you WILL find it!