The stepdaughter is Renata, a monstrously obese thirteen-year-old, victim of an obsession which settles in around the girl like a noxious mist and lifts too late. The stepmother is ""K,"" through whose letter/diary the days' torments inch on; husband Arnold has left her desolate, with a gleaming Manhattan apartment (does a ""velvet coffin"" have a view?), an unhappy au pair girl, their four-year-old daughter--and Renata, whose mother, Arnold's alcoholic ex-wife, is hospitalized in California. Imprisoned in the apartment, K's self-loathing and her rage at Arnold's quicksilver manipulations squirm up in her mind by spontaneous generation, and she transfers her pain to Renata, whose vulnerable, passive hulk ""invites a kind of cruelty,"" seeming to be a manifestation of all that is gross, evil, and unfair. Only when Renata is forced to divulge that she is no one's child, shunned even by Arnold (who is not in fact her father), does K touch reality and the possibility of compassion. But it is then that the stepdaughter, with an odd gallantry, relinquishes her last claim to belonging and disappears--and she will never be found on the ""cold, savage streets of New York,"" this girl who has been made to feel that ""her whole life was nothing more than an undesirable accident."" This is a close, almost stifling--but potent--view of dangerously vengeful predators caught in the act of cannibalistic plunder.