The meaning of the novella's title, The Beast in the Jungle, becomes clear in Chapter 2 during a lengthy description of Marcher's convictions about his own fate:
Something or other lay in wait for him, amid the twists and the turns of the months and the years, like a crouching Beast in the Jungle. It signified little whether the crouching Beast were destined to slay him or to be slain. The definite point was the inevitable spring of the creature; and the definite lesson from that was that a man of feeling didn’t cause himself to be accompanied by a lady on a tiger-hunt.
The simile here is "something or other lay in wait for him [...] like a crouching Beast in the Jungle." In other words, Marcher's fate, the unknown "something," awaits him among the twists and turns of months and years just as a tiger would await its prey in the leafy thickets of a jungle. Notably, the words "Beast" and "Jungle" are capitalized, as if to solidify their importance in the form of proper nouns. Indeed, Marcher shows great deference to the Beast, whose (imagined) presence haunts him until the final pages of the story. This powerful simile compartmentalizes the whole story in a single moment of comparison. However, as the reader later discovers, the "Beast" of fate turns out to be a tragically bland result of waiting rather than taking action. When May dies, the fate that once seemed exotic and terrifying becomes anticlimactic and sad.
By comparing the knowledge of Marcher's fate to a hump on his back via simile, the narrator demonstrates the omnipresent effects of this new knowledge. This comparison appears in Chapter 2 amid a description of the growing friendship between May and Marcher:
Such a feature in one’s outlook was really like a hump on one’s back. The difference it made every minute of the day existed quite independently of discussion. One discussed of course like a hunchback, for there was always, if nothing else, the hunchback face. That remained, and she was watching him; but people watched best, as a general thing, in silence, so that such would be predominantly the manner of their vigil.
In Marcher's time, a hunchback was considered at worst a deformity and at best a curiosity. Just as a person with a hunchback might feel alienated from society as a result of his unique physical feature, Marcher feels alienated by his own fate. It continuously reminds him of the (imagined) gulf between himself and others, and thus it makes a difference "every minute of the day." It need not be discussed because it remains so firmly in Marcher's mind.
This simile also evokes another similarity between Marcher and a person with a hunchback. Just as a hump on one's back affects one's other physical features, Marcher's mental state characterizes his speech and affects the way that he communicates with May, who of course knows the weight that fate carries in his mind. This comparison of a mental preoccupation to a physical deformity allows the reader to more clearly envision the impact that Marcher's fate has on him and his interactions with May. It also gives the impression that fate is something heavy, unavoidable, and unwanted, but it also largely determines the course of the protagonist's life.
At the beginning of Chapter 4, the narrator foreshadows May's death with a chilling description:
[...] May Bartram sat, for the first time in the year, without a fire; a fact that, to Marcher’s sense, gave the scene of which she formed part a smooth and ultimate look, an air of knowing, in its immaculate order and cold meaningless cheer, that it would never see a fire again. Her own aspect—he could scarce have said why—intensified this note. Almost as white as wax, with the marks and signs in her face as numerous and as fine as if they had been etched by a needle, with soft white draperies[...]
This scene foreshadows her death in a few different ways. First, there is no fire in the hearth, and the narrator says that May seems to know that she will "never see a fire again." This indicates that she will live for less than a year. Second, her skin is "as white as wax," a simile that suggests her illness and imminent death. Third, the story's diction changes slightly to include many words that allude to death, including "sadness," "ultimate," "cold," and "meaningless." These three elements combine to foreshadow May's death, and accordingly, she ends up dying from a blood disorder soon afterward, taking her love for Marcher to the grave. This moment of foreshadowing also marks a downturn in the text's mood and reflects the themes of love and loss while anticipating Marcher's regret at never having loved May.
