"To answer the question "What's the point of any of this?", we must first break it down into parts, evaluating each of their meanings in turn. First, "what's"; a contraction meaning "what is". "What" is the subject of the interrogative sentence in question; "is" is the main verb. "What" is a pronoun indicating that the sentence is asking for information, an example of similar use would be the sentence "What will you eat for dinner?". "Is", a conjugated form of "to be", indicates the following phrase will represent the information being requested by the question; in this case "the point of any of this".
Having established that the answer to this question must be the information which could be said to be "the point of any of this", we must find the meaning of this objective phrase. "The" is the definite article, meaning the noun phrase it belongs to refers to a particular noun; "'The' point of any of this" would be different from "'a' point of any of this". "Point" is possibly the most complex word found in the question we seek to answer, as it has a multitude of meanings with often no relation to each other, and as such will be addressed later. "Of any of this" is a prepositional phrase with a second prepositional phrase nested inside of it; while its structure may be complex compared to the other phrases in the sentence, the meanings of "of" are related to such a degree that the phrase is fairly simple to analyze.
"This" can play the grammatical role of an adverb, a determiner, or a pronoun; however, the first two are easily eliminated in this context, as "this" cannot be modifying any other word in the sentence, as it would in use as a determiner (e.g. "get a load of 'this' asshole") or an adverb (e.g. "I can't handle food 'this' spicy"). As a pronoun, "this" indicates a specific thing or situation--one that must be fresh in the memory of the reader to have proper meaning. In this specific case, the most memorable situations would be the girl drawing shapes upon her paper and the subsequent ruination of said drawing. However, the context of "this" in the question points to another possibility.
The prepositional phrase, "of all of this", hints that it is not important what part of "this" we provide an answer in relation to. In questions, when used as a pronoun and followed by "of", it refers to a nonspecific part of the object of the prepositional phrase beginning with (in our case, the second) "of", without regard for which part is addressed; one part is as valid as another. It is possible, then, that "any of this" refers to anything at all, and the question could be rephrased to "What's the point of anything?"
"Point" can refer to a unit of measurement used in the realm of typefaces; for instance, I am currently typing this answer in a computer program called Notepad in 11-point font. While it is difficult to imagine this as the intended meaning of the word in the question, if we stretch the meaning a bit, one could imagine the question asking what size font "any of this" is written in. Equally unlikely, if not more so, is the word "point" in the question referring to a unit of score, as would determine a victory in one of many sports or other games, or else measure one's achievements. It is difficult to determine a meaning for "the point of any of this" in this context, unless perhaps one is asking which of one's actions would score a point.
A "point" can also be a place in space, or in geometry, with no dimensions. "The point of any of this", or "the point of anything", in this case, could be a point where one could locate anything, and could only refer to the singularity supposed by scientists to have existed before the astronomical event known as the "big bang" which resulted in the rapid expansion of that point, eventually leading to the universe as we know it. However, it is unclear why one would ask what the pre-big bang singularity is. Similarly, it can refer to a single moment in time,
but unless the girl is asking the time at which she was drawing or when the drawing was ruined, this leads to a meaningless question.
It can also refer to a pointed end or part of an object of any sort, as in the point of a sword or the end of a peninsula or other geographic feature such as the summit of a mountain. It is unclear what meaning the question would have in this context, as the girl isn't looking at her paper to see any pointed shapes drawn on it, nor the point of her pencil, nor any incidental point a part of the paper may have tapered to when it was crumpled. It can also refer to an aspect or area of a greater whole in contrast to the whole, such as in the sentences "Tact is not one of her strong points." and "There's this giant enemy crab, and you attack its weak point for massive damage." However, "the point" without any adjective or phrase modifying "point" does not lend itself to this particular meaning, as there is no contrast between "the point" and "any of this".
This leaves us with the most likely intended meaning of "point": a meaning or purpose, as in the sentence "You're not even reading this, so there's no point in me continuing to write it." (This sentence may or may not be the truth, in relation to this message as a role claim for a game of Mafia.) Were the girl asking "What's the point of this?" it would be likely she would be referring to the drawing she just ruined, but the inclusion of "any of" suggests a broader, perhaps more philosophical meaning to the phrase. The girl's question belies a deeper frustration than merely that with her ruined drawing if she is so deeply troubled as to ask for the meaning of "any of this" rather than merely "this"; likely, she is searching for meaning in her life, possibly even questioning whether or not there is any.
This question is one philosophers have striven to answer since the earliest civilizations, and for which a multitude of answers have been proposed. Even among the Ancient Greeks, several answers were derived, including attaining the highest form of knowledge, creating a great amount of happiness, living a life of virtue in harmony with nature, attaining tranquility and freedom from fear, freeing oneself from suffering through clear judgement, and likely several others less documented.
The philosophy of the Age of Enlightenment which dominated Europe during the 18th century provides further answers, but for the purposes of this role claim we'll ignore them for a couple reasons--first, I've written over a thousand words worth of quite frankly nothing already, and second, I don't even like Enlightenment philosophy. For instance, did you know one of the age's most influential philosophers, Immanuel Kant, rejected the idea that the consequences of an action were at all important to that action's moral value? I know! I know. It's ridiculous, isn't it? While the ridiculousness of Kant's Categorical Imperative, as he called it, may strike a chord with players in a game of Mafia, the real-life implications of his absolute morality are difficult to reconcile with reality. I really just want to get to Existentialism and Absurdism and be done with this, but we still have a whole century left to cover before that, don't we? Sigh!
In the 19th century, Jeremy Bentham proposed the Principle of Utility, which proposes that actions are good if they, overall, increase pleasure and reduce pain, and are bad if they do the opposite, with the meaning of life being the betterment of the world through the creation of pleasure and reduction of pain. Around the same time, nihilists suggested that there was no objective meaning to life, a grim prospect.
The discord between this lack of objective meaning in the universe and a person's inherent wish to find meaning gave rise to what philosophers call "absurdity", in this case referring to the specific dilemma which must be resolved. Philosophers such as Søren Kierkegaard and Albert Camus alleged there are three ways to resolve the condition of absurdity, though they disagreed as to the "correct" choice in the matter. The first method of resolving absurdity is suicide, which ends the dilemma by ending one's existence itself. I do believe we all would agree that this is not a viable answer; loath as I am to come so near to invoking the Categorical Imperative, were we all to choose this option, there would be nothing left.
The second option for coping with absurdity is to believe something exists beyond it, that something somewhere transcends the existence that we experience. Camus referred to this option as "philosophical suicide", as undesirable as plain suicide, while Kierkegaard and others refer to it as "religion". Kierkegaard, himself a Christian, considered this the righteous path toward freeing oneself from absurdity.
The final option, regarded by Camus as the correct one and by Kierkegaard as "demoniac madness", is to accept the Absurd and continue to live despite it, possibly even embracing it. This is similar to the Existentialist assertion that "existence precedes essence"; that is, before one exists, there can be no meaning to one's life, because one must make one's own meaning. There are many variations on what exactly this means, but the essence of Existentialism is that each person must create their own life's meaning for themselves.
Put simply, neither I nor anyone else can answer this question for this girl, who must find her own way. While this may seem a grim outlook to some, I would argue that it is in fact quite liberating; while one could say that the world is inherently meaningless, one could also say (and, in fact, I would say) that because of it, this girl is free to forge her own meaning, whatever she might want it to be. You do you, girlfriend. You do you."