Since I already did a full review of this back when it first came out, I'm going to restrict my words on this to comments about things I noticed or found interesting during the second playthrough (setting aside spoilers).

First... Zephyr.  As a protagonist, he is the kind of guy most people would love to hate.  In Japanese, he frequently refers to himself with blunt internal honesty (and outwardly to others as well) as '小者’　and ’凡人’ (words that basically mean he is the lowliest of 'normal' people).  His primary directives are living low profile, staying away from trouble, and avoiding things like victory and defeat at all costs.  However, the moment he's backed into the corner, he becomes a psychopathic murderer who will do anything to survive, including humiliating and killing others painfully.  He gains a dark pleasure from seeing people better than him fall into ruin, and he is the farthest thing from a hero that you can possibly imagine.  It is a mark of the skill of the writers in this VN that he is actually likeable anyway, lol.

Second, Millie.  To be honest, she is basically the Kasumi (Dies Irae reference) of this VN.  She is warm and loving by nature, a representative of the life that Zephyr wants to live as well as the one person he would willingly do anything to protect (including die, which says a lot considering his abnormal attachment to life).  Chuunige makers almost compulsively include at least one heroine of this type in their games, because the rest of the heroines are usually somewhat psychopathic, broken, or otherwise outside of the norm.  That she is also actually 'useful' in the VN is a plus point in her favor, as such heroines go.

Third, Chitose... Amatsu Oboro Chitose is my favorite type of chuunige heroine, the type that mixes love, hate, and obsession in varying amounts when it comes to the protagonist, but still retains her sense of self nonetheless.  She is the elite of the elite, a thoroughbred warrior-leader who lives for her work (which is killing people and administering judgement/justice).  Her attachment to the protagonist might seem weird to someone not used to the somewhat twisted relationships common to action-fantasy VNs, but this kind of heroine is an absolute treat for those of us who are experienced in the genre.  Also, a warrior-type that is not a straight-laced, unaware-of-her-own-feelings type heroine is nice indeed.

Fourth... Vendetta.  I'm going to be blunt.  Do-S eternaloli.  Rusheed's obsession with her (since he is a do-M lolicon) is perfectly understandable, and she also works out nicely as the game's true heroine, as she has that peculiar inherent sense of tragedy and loss that true heroines in good chuunige tend to have.  Unfortunately, talking about her any further would ruin it for those who haven't read the VN yet.

Fifth, Valzeride.  This guy is a primary antagonist and the hero of Adler, the country (and city) in which this VN is based.  I'm going to be blunt... in any other chuunige VN, this guy would be the protagonist.  I'm not kidding.  He is upright, outstanding, utterly capable, and honorable to a fault, within his own sense of personal morality.  He is Zephyr's antithesis and the contrast is actually a pretty significant issue in the VN.  Even if this guy weren't the protagonist in another chuunige, he would be the one who dies to save the world, leaving the protagonist and everyone else to weep in loss.  If this guy were ruling my country, I'd probably join the military too, lol.

I hope this gives those interested - or not yet interested - in this VN an idea of what the primary characters are like, lol.