The Menstruating Mall

This novel reminds me of Agatha Christie "And then there were none" (or the original title "Ten Little Niggers"). A group of persons are locked together in a place and they are dying one by one. Who is the killer?
Each character is a parody of a person Carlton Mellick met. There's a white boy who thinks he is black. There's a girl self-absorbed, a gothic who isn't really a gothic, a jockey who turns out to be gay or our main character who is an addicted to shopping and working. There is also a couple of other characters that get almost none cameo like the soccer mom, the cowboy or the fundamentalist. Interesting or not a black punk is also present and it's one of the main characters.
We get to know each character and it's story and they are almost all funny even if some are too 2dimensional. Of course I want to believe that it's done on purpose or Carlton is just a bad writer.
The book as almost 200 pages but each chapter has only one or two pages. There are also some drawings of publicity but I found them ridicolous and without any link to the story.
As the story progress I started reading faster and faster and I hope my train to Sintra had a delay (which usually has) so I could read a little more before arriving at home.
I really enjoy the first two parts. I don't know but I think Bentley Little could grab this book and make one heck of novel. The last part of the novel it's dry as a desert and I didn't enjoy at all. This is the second book by Carlton Mellick that I found the ending uninteresting.
Would I advice it to someone? To the Bizarro funs. Or to anyone who want's to try something new.