If I understand Shem correctly - not having read the book in question - then chicklit snark is basically something that is snarking chicklit.
Chicklit is a term to describe literature aimed primarily at women, mostly, that is, romances and romantic comedies, of various eras.
Snark or snarking means to poke fun at something or parodying it, both lightly and in good humour as well as deeper and more seriously. This doesn't only mean literature, but also, for example reviews or other discussions.
If you will, Northanger Abbey is an example of chicklit snark, because it pokes fun at the conventions of gothic novels (which were of course also read by men, but seem to have been a great hit with women).
Hope I got that right ;-)
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