The most obvious and omnipresent theme of G Senjou. Not "what is evil?", but rather, "how and why does evil come to exist?" The major players of G Senjou can be divided into three different types:
- Those who fear and hate evil
- Those who become seduced by evil
- Those who are masters of evil
The ones who hate and fear evil are those who are unwilling or unable to dirty their hands with evil means. Tsubaki is the most obvious case; her mind simply cannot comprehend a world in which people are not intrinsically good. Eiichi is the other easy shoe-in for this category as he likes to talk up how much of a player and mastermind he is but deep down, he is a good person who shies away from doing anything truly wicked. Naturally, this category includes most of the main characters. It's not that they don't do evil things but they believe themselves, for the most part, to be good people. The contradiction in this kind of thinking is pointed out by the game several times but that is something we will get to later.
Then we have the people who have become seduced by evil. This is the category for most of the minor villains of the piece, as well as our protagonist himself, Azai Kyousuke. These people brush the surface of evil but that's as far as they get. They are slaves to their own desires, whether it is for money, fame, recognition or whatever. It is these people that Maou calls his "children" and Gonzou calls "livestock", mere pawns to be used in the games of their betters because they have no vision or purpose of their own, simply seeking to gain as much as they can before dying, most likely alone and forgotten.
Finally we have the masters of evil, the people for whom evil is a means to an end rather than an end itself. The people in this category, naturally, can be counted on one hand. They are the ones with the vision to make things happen, the masterminds, the ones who really have power. Now, what does this have to do with the story?
The main question posed by the game, as mentioned above, is, "how and why does evil come to exist?" People usually, for whatever reason, hate and fear evil. They try to obey the law, do what is just and right, and generally live normal lives but on the fringes of society where there is much less support and love to go around, these same people may become seduced by evil, typically in the form of one of the masters of evil. Nothing is beyond the corruption of evil and even those who have the best of intentions can have their thoughts subverted when confronted with the supposed flaws in their logic. For instance, Tsubaki's extended conversation with Maou showed that her thinking was seemingly altruistic but in reality, it was hypocritical and selfish.
This is why the recurring theme of Der Erlkönig is so important. Yes, it is connected to classical music through the Schubert interpretation, and yes it serves as a metaphor for the playful, fey nature of Maou (contrary to the game's interpretation, the Erlkönig of the poem is generally considered to be one of The Fair Folk rather than the Devil himself although, since Japanese mythology doesn't really have any equivalent of fairies, Devil works just as well), but how does this relate to evil? "Der Erlkönig" was originally written by one Johann Wolfgang von Goethe, a man we normally associate with Faust. Now, Faust is more relevant to the subject of man and evil, and is alluded to occasionally within G Senjou. It may seem like a tenuous connection and a bit of a western-centric view but given that virtually all the leitmotifs in the game are European classical pieces and the numerous Faustian bargains within the story, it is difficult to think that the significance of the original Goethe poem would be lost on the writers.
Now, what was it that caused Faust to become corrupted in the first place? In the end it was his own desire and thirst for knowledge that caused him to strike his pact with the Devil rather than anything the Devil actually did. The same is true of those who became seduced by evil in G Senjou - Kyousuke did it so that he wouldn't have to be poor, no matter what excuse he gave about his mother. Yuki did it for knowledge. In the end even Haru jumped off the proverbial precipice in the name of revenge. There isn't a single person in G Senjou who wasn't corrupted as a result of their own desires and these subconscious, wicked, selfish thoughts are frequently referred to as "the Devil" inside the people (see Tsubaki and Kanon's routes). When you think about it that way, Maou is not simply an affectation to look cool or an epithet to spread fear. There's no conceit there. Maou is literally the Master of Devils, the desires inside all people.
It has been said, occasionally, that love will be our salvation. It will set us free. To an extent that's true. After all, in four out of four routes the protagonists were able to achieve their happy endings because of their love for each other, giving them the strength to overcome their own flaws. Such a theme is not uncommon in visual novels. On the flipside, love can also be one of the greatest motivators for someone to turn to evil. After all, even Maou himself was driven by revenge for what was done to his loved ones. Hashimoto wasn't a bad person either, even he loved his dad, enough that he would start taking hostages so that he could be released from prison. For love, Mizuha would have thrown herself into the pits of hell and cast her lot in with her sister without ever realising what she was getting into, and stood in front of Kyousuke, willing to risk being raped. All for love. Were it not for the goodwill of others she would have been damned (and that's exactly what happens in the Bad Ending for her route). So you see, it works both ways. Love can save us or destroy us, if we let it.
A phrase from the poem is used throughout the story. It reads, "Come, lovely child! Oh come thou with me! / For many a game I will play there with thee!" The easiest interpretation is as mentioned above - it is a phrase that sums up perfectly the mischievous nature of Maou and his love of playing mind games with Haru and his other victims. But astute tropers who have read The Fair Folk page will know that there is certainly an even more sinister interpretation to his portrayal as the Elf King. There is nothing human about Maou's capacity for cruelty or planning, the way he hand-crafts each and every one of his pawns and then casually expends them in a display of supreme violence. The humanity that Maou used to have has all been stripped away by years of war and hatred. He should be dead but he's not. He should feel something when toying with other peoples' lives but he doesn't. Kyousuke tries and is only able to reach that unnatural state with considerable effort in suppressing his emotions. That is why we have the Bad Endings. Also of note is that Maou tends to work with children, mirroring the legend of fairies taking children from their parents for their own inscrutable purposes.
Air on the G-String
A piece conspicuous by its absence in the story. Air is only heard during moments of exceptional poignancy, despite being the inspiration for the title as well as Kyousuke's favorite song. But perhaps that is the point. Because of Haru's lifelong grudge against Maou, she can no longer play Air on the G-String. Thus, until the end, we don't get to hear it.
Issues with an Analysis
Of course, we must also keep in mind that everything written here might be complete BS. For someone who doesn't know or understand Japanese cultural attitudes, it is entirely possible to misunderstand something that would have seemed self-evident to an ordinary reader. The themes may have been interpreted in a way the authors never intended, and thus the analysis may have taken on a life of its own and grown into some terrible abomination. But, of course, this is why analysis is sometimes called "critical appreciation".