It would be tempting to think of Jenni Fagan’s memoir as a skeleton key to her fiction and poetry. There are certainly echoes. The descriptions of “units” resemble the sinister spaces in which the protagonist of The Panopticon is confined (there is also a reference to roadkill for those with an eye for detail). The caravan park has a clear rhyme to the one in The Sunlight Pilgrims, as does the litany of multiple deprivations. Like Luckenbooth, there are scenes of depravity and the strange pleasure of what Virginia Woolf would call a room of one’s own. There are repeated references to being a witch – therefore unfairly excluded or shunned or feared – which chimes with the novella Hex. But though it is possible to trace the connections, it would be wrong to think of this as “this is where my inspiration came from” writing.

I have followed Fagan’s career for a long time now. Indeed, I was on the panel that made her a Granta Best of Young British Novelists author, on the basis of one book. It is always difficult when you have backed a writer with the future career sight unseen (in all honesty, I think The Sunlight Pilgrims is her strongest work, and also the most fictive). But Ootlin is something entirely different, and far more visceral.

The memoir begins with a startling statement. “Twenty years ago I began writing this memoir as a suicide note and as I was trying for hours to sum up my life in one small letter all I could think was – is that it?” There is certainly a lot of “it” in it. The book encompasses abuse, casuals, booze, drug use, child prostitution, an attempt at suicide, body shaming, prejudice, and many other horrors. Throughout Fagan appears to excel at school except when she is so wrecked she nearly misses a court hearing. Much of this is familiar from Irvine Welsh’s needle-novels and Douglas Stuart’s wistfulness at poverty. Fagan is much more forthright, and in some ways, I wish this had been a polemical pamphlet about the care system. Saying “this is a story about stories” takes the edge off “no, this happened to me”. Such self-conscious literary devices can be distancing, and yet when the book gets underway, I found myself – a first – wanting not to read. It is almost too sad and too terrible. I would never call a book like this enjoyable, or entertaining, or joyous. I rather doubt Fagan would either. This is a work wielded as a weapon.

Stylistically, a reader with an aversion to exclamation marks might shrink a little. In the sections about her earliest life they seem apposite – most children point and smile. It seemed to me similar to how James Kelman modulated his syntax and grammar in Kieron Smith, Boy. but in the later sections they come across differently, as steely in their defiance. They are the punctuation equivalent of a pair of raised fingers.

Ootlin is a supernatural entity, and the memoir is threaded with such references. “In lieu of other names they called me ootlin. One of the queer folk who never belonged, and outsider who did not want to be in”. There are the dead, and ancestors, and goblins, and monsters. But the real monster is bureaucracy. By the age of five, Fagan had lived in over a dozen homes. She is not even originally named Jenni. While the gothic overtones are effective, the scrupulous look at how the state deals with children who were “dealt her hand”, as it were, seems far more important. There are good people within the system, there are also psychopathic ones. It seems obvious why the memoir does not mention specific names.

At the end of the book Fagan writes, “I am still here and I care more than ever” – care is a loaded word in this – “I am angrier than I have ever been, and I admire every person who takes a stand in small ways, in huge ways, without applause. It is not meaningless; we are the story – all of us – for as long as we are still here”. Although the book is subtitled “A Memoir”, “A Polemic” might be more appropriate. Even getting access to government documents about herself proved to be punishing. The state renamed her and never told her her name.

Disgust is a difficult word. There are descriptions in this book of truly disgusting behaviours; yet it is possible to feel righteous disgust at a broken and failed system for the most vulnerable. It is also honest – the sections about how good it feels to get out of it are remarkable. Fagan captures the delirium and disorientation of the experience with the clarity of hindsight, and does not flinch from saying it gave her a crumb of happiness in an otherwise wretched world. This book leaves open one question – an inveterate writer having written what she would not write, what will she write next?

Ootlin: A Memoir, by Jenni Fagan, Hutchinson Heinemann, £16.99. Jenni Fagan is appearing at the Edinburgh International Book Festival on 25 August

Book review: Ootlin: A Memoir, by Jenni Fagan