One word: bleak.
All right, this book deserves more than one word. It is very much of its time (a 1960s description of, and attack on, pre-Quiet Revolution rural life in Quebec, nasty, brutal, and Church-dominated), but it also has a poetry about it. That's particularly true in the inset autobiographical narrative by Jean Le Maigre, one of baby Emmanuel's 15 siblings, and the real protagonist of most of the novel, until his predictable death about 2/3 of the way through. Jean is a dreamer and a writer; his sister Heloise is an ecstatic postulate in a nunnery until, having been expelled, she becomes an almost equally ecstatic prostitute. Two other brothers also have major roles: "Number Seven" (Septieme), who almost never gets his real and ironic name, Fortuné - he finds his individuality in a life of petty crime, and "Pomme", who is the family sacrifice to uncaring industrial abuse and accident. Two contrasting women keep this family going, mother and daughter: mother (Grand-mère Antoinette) has somehow managed to maintain such energy and such decency as exists in the world (she brings sheep into the house when it is too cold outside), though her outlook is very limited. Her daughter, who is never named, except as "the mother" of the 16 children, is silent and exhausted. The father of this family does little except give his children regular beatings.
At various times, we see the children packed off to the different institutions of their homeland - a reformatory, a seminary, and (for Pomme) a factory. All are grossly injurious. In comparison, the incestual sexual pleasurings of the three brothers seem innocent. Even Heloise's brothel is cheerful by comparison.
But in the end, as I say, it's pretty much all bleak - as much bleakness as you could possibly imagine being crammed into 145 pages. Emmanuel doesn't have much to look forward to, even if winter is over and spring is starting at the end of the novel.