In just two years the pair have gone on to write a column for the New Statesman and a number of articles for the Guardian, as well as keeping up their blog which features posts such as "Why Cosmo's Wrong About the Thigh Gap" and "The Problems With Frebreezing Your Fanny".
The book picks up where the blog first began, exposing the "minefield of misinformation and manufactured self-loathing" promoted by women's magazines.
The Vagenda takes endless snipes at headlines such as "The seven kinds of orgasm that you absolutely must be having right now", and mocks magazines' endorsements of ludicrous products from semen facials to caffeine-infused tights.
Beneath its irreverent tone, the book voices a real fear about the lack of "normal women" represented in the media. Cosslett and Baxter urge magazines to write more honest features about sex and relationships, and to stop their endless scrutiny of women's bodies.
The book makes a number of valid points about the media and its role in defining modern womanhood, but the arguments often feel rehearsed. The Vagenda rarely expresses anything new that has not already been debated in the online discourse about modern feminism that has exploded in the past decade.
Slut-shaming, the pubic hair removal conundrum and the detrimental effect of Photoshop on girls' self-esteem are all important issues to address, but have already been written about tirelessly in the media and are offered here again with no fresh perspective.
The book lays bare the large commercial contracts between beauty companies and magazine publishers, highlighting contradictory editorial layouts that see articles exposing the dangers of cosmetic surgery followed by adverts promoting liposuction.
The sexualisation of young women in music videos, the idealised image of beauty endlessly promoted on social media and the number of Female celebrities "flaunting their curves" on the Mail Online's "sidebar of shame" get little mention compared to frivolous headlines in Cosmo.
For all its claims to be a "call to arms for young women", The Vagenda feels more like a six-figure ploy on behalf of publishers to capitalise on an already established online presence, rather than a concerted attempt to give a new perspective on feminism.