It is no secret that I am a huge Higashide Yuuichirou fan and that Evolimit is my favorite Higashide Yuuichirou game. Before I go any further into this, I should note that Evolimit has the dubious honor of being the VN I've played the most often... a total of six times, as of two hours ago. I should also explain what Higashide's unique qualities are as a writer.
Higashide Yuuichirou wrote six VNs for Propeller before retiring from VNs completely to work for Type-Moon as a writer. He also worked on the Vita version of FSN, with the Caster and Rider routes, the Muramasa FD, Princess Waltz (as an assistant), and Fate/Extella Link. His qualities as a writer include a peculiar genius for the characterization of 'heroic' characters, the ability to create villains/antagonists worthy of those same heroic characters, and an even rarer ability to both write and integrate SOL with those aspects. For better or worse, most SOL writers fail utterly when it comes to dramatic characterization and most chuunige writers suck at SOL compared to specialists. However, Higashide manages to do both at a very high level and, when he is 'in the zone', does it better than any other writer I've encountered.
Some will argue with me about this, naming Shumon Yuu, Masada, or even Hino Wataru. However, it needs to be said that Shumon Yuu writes in a manner that is so unique that it is completely genre-free. Masada writes excellent dramatic characters, but his SOL is average at best. Hino Wataru tends to shift the balance of his games back and forth, and there is usually a huge gap between the quality of the paths of heroines he loves and those he merely likes.
I have never felt like Higashide has failed to give a heroine a fair shake. In fact, Higashide almost never makes heroines the true focus of a game/path from beginning to end. Circumstances, events, the protagonist, the antagonist, and the pattern as a whole often far transcend the heroine of a given path. His heroines are often good, but I've yet to encounter a path in a Higashide game where I felt cheated.
Higashide is a devout follower of the concept of the 'heroine that is always by the protagonist's side, no matter who he chooses'. This type of heroine pops up in a lot of chuunige. Kagome in Comyu is probably the most blatant example of this, but Higashide takes it to extreme lengths. In Ayakashibito it was Suzu, in Bullet Butlers it was Selma, and in Evolimit it is Shizuku. The key point of each of these heroines is that the bond with the protagonist transcends romantic relationships (though it leads to them in their own paths). Suzu is both parent and older sister to Soushichi, Selma is Rick's master and truest friend, and Shizuku and Shiranui are ridiculously close friends, so close that they easily settle into a familial role toward one another. Why is this important? Because these characters and their relationships form the largest and firmest pillar that serves as a backbone for each of these protagonists' view of the world and how they relate to it.
Evolimit is a kamige. Yes, that is my opinion, but I'll stand by it until the end of days if necessary. For this entry, I'm going to focus on characters, their interrelationships, and their influences on one another. From here on in, I will intermittently add in spoilers, which I will put in boxes. These spoilers will often reveal aspects of the story you absolutely do not want to know until you've played the game, so I recommend just reading the parts that aren't spoiler-boxed and going back after you've had the opportunity to play the game.
Shiranui (nobody calls him Yoshikazu, interestingly), is an interesting character. Like the other two Higashide kamige protagonists (Ayakashibito's Soushichi and Bullet Butlers' Rick), he is, when it comes down to it, a classic hero. He is the type who will, without hesitation, throw away his life for others if it comes down to it, take a bullet for a friend, or mercilessly destroy someone or something that seeks to harm them. Since this is revealed in the prologue (and my rules about spoilers don't apply to prologues), I'll go ahead and describe his basic set of circumstances.
First, Shiranui was one of the Calamity Monkeys, the first colonial/terraforming expedition sent to Mars by the more-or-less unified governments of Earth. Born with a bad heart, he spent much of his youth in horrible pain and fear, wondering if that day would be the day his heart went out. However, he received a heart transplant, and soon after he encountered Kokoro, the spiritual remnants of the young Chinese girl who was his heart's original owner. The reason I reveal this particularly dramatic element in advance is because it is necessary to describe his peculiar personality.
On the surface, Shiranui is a slightly pervy young man with an ever-present smile who goes out of his way to be something of a clown. In stressful situations, he is surprisingly perceptive, brave, and compassionate. However, there is one peculiarity that is all-important to grasping his character.
He is incapable of sorrow.
The reason goes back to the spiritual remnant of his heart's original owner, Kokoro. In order to allow her to remain within him, he, of his own free will, gave up his ability to feel sorrow (as well as odd bits and pieces of other emotions) in order to allow what amounts to a second person to inhabit part of his brain. She is also the reason he chose to head for Mars. When he discovered that her dream was to go to Mars as part of a colonial expedition he, without hesitation, chose to take the baton and run with it, ferociously devoting himself to the duty of taking her there as part of himself.
During the trials to become one of the colonists/terraformers, he met Ichijou Shizuku, a fellow aspiring colonist (and an all around genius) and befriended her. That friendship deepened to a ridiculous degree as the number of aspirants fell, reducing from around ten thousand to forty-five hundred, to around five hundred at the end. Brutally hard physical training and tests, psychological examinations, sociological studies, and constant testing of their knowledge are the things mentioned off-hand... meaning it was probably even worse to experience, lol.
After arriving on Mars, he formed close relationships with six other fellow colonists. These included the powerfully charismatic and brilliant Shannon Wordsworth; the rough-mannered former soldier and geologist Dmitri Kalanikov; his biologist daughter Tsunami Kalanikov; a genius robotics engineer, programmer, and African-American Tyron Bistwark; a Swedish doctor and psychologist named Maya; and Hoan Wenchui (incidentally, I'm uncertain of the actual best romanization for his name, but meh), a Chinese man of the same age. It was these relationships that formed the center of his early experiences on Mars.
His relationship with Kokoro, who is his heart donor, is the closest one from the beginning, including Shizuku. This is obvious, since she is quite literally part of him, his motivation for trying to reach mars, his oldest friend, his first love, and perhaps the single best female character in the game. His love for her is so much a part of his life that, in most cases, he cannot even consider giving up on her even to save the life of his lover of the time. There are endings where he does choose to move on from her... but this is always initiated and encouraged from Kokoro's side and it inevitably scars him deeply in the process. It is a mark of how powerful she is as a character that two of the three heroine paths have endings defined at least partly on whether he decided to lose her in order to gain the power to save his lover. Kokoro herself is easily the wisest character in the game, with a unique outlook born from being an eternal observer.
Shannon Wordsworth was Shiranui's mentor. He was a brilliant but inscrutable man with a dark past, a definite charisma, and a near-infinite curiosity. He is also, despite indications otherwise in the various paths, completely and utterly sane. He is a man who, once he discovers what he wants, will do anything and everything to obtain those desires, up to and including sacrificing friends and companions and causing them immense suffering. It isn't that he doesn't care. He feels guilt, he feels sorrow, he feels regret... but he doesn't even consider stopping. His desire to pursue his dreams is prioritized over all things, and it is an aspect of his personality that is reflected at least somewhat in Shiranui himself.
Tyron Bistwork is a brilliant man who desires nothing more than a future where intelligent robots are friends with children. However, like all three of the adult Disasters other than Shannon, his love for humanity was twisted by Shannon's manipulations so that he believed forcing humanity to face him and the others as a tribulation and a test was the best thing for humanity as a whole. Tyron is a playful child in a lot of ways, often modifying his machines or playing tricks on people on a whim. This remains when he becomes Earthquake in his development of Hecatoncheir, a giant Barbaroi robot with a giant plasma cannon, multiple Patches, and the ability to learn.
Dmitri Kalanikov is, at his core, the most heroic character in the game. Oh, he is also a villain. That is inevitable, considering the role forced on him. As Volcano, he was the most obsessed with putting humanity to the test... but that was due to his incredible love for humanity, twisted as it was by Shannon's manipulation of his psyche, as well as his daughter Tsunami. Before his transformation, he was very much the doting father, the cheery leader, a man of courage who stood out amongst other men of courage. It needs to be said that, if I had to name a character outside the central cast (Shiranui, Shannon, the heroines, and Kokoro) who should be considered the game's MVP, it would be him. His death in Shizuku's path left such an impression on me that I find myself comparing all other sacrifice scenes to it, no matter the anime I'm watching or the game I'm playing.
Maya leaves the weakest impression of the Disasters. Part of this is because she is quiet and retiring by nature, part is because she lacks the ferocity, the fire of some of the others. In a cast of characters burning with passion, she is a woman of gentleness, kindness, and compassion. However, this very kind nature is twisted against her by Shannon when he transforms her into Avalanche, making her believe not only that the trials are the best thing for humanity, but that her actions are a mercy. She is the most self-aware of the Disasters (excluding Shannon and whereas Tyron is the least), and Higashide uses this poignantly to demonstrate just how thoroughly the psyches of the three are manipulated.
Kou is insane. He is, in fact, the only character in this game that can really be considered to be insane. The reason I say this is because, for the most part, he can't tell the difference between his hatred for humanity and his hatred for Shiranui. Kou, before he discovered that Shiranui has Chenfui's heart, was a mildly misanthropic young man who nonetheless managed to be cheerful and friendly within the small circle of friends he had made. However, the fact that Shiranui was his closest friend made his hatred all the stronger when he discovered the truth about it. For this reason, almost every scene involving him and Shiranui is intense and emotional... and heartbreaking. It also makes the 'Departure of the Calamity Monkeys' in Shizuku's second and third endings all the more poignant, since it is the only path where brother and sister reunite and are able to talk directly, even if it is only for a brief time before they go to their eternal rest.
Pochi-sensei is a character that is typical of Higashide... he loves to include talking animals in his games, and Pochi-sensei is, in my opinion, the best of those. He is intelligent, wise, and warm-hearted. He is a teacher to the core, educating, protecting, and watching over the students as the school principal for Forsyth. He is also incredibly cool in battle and a wonderful supporting character.
Kazuna is an interesting heroine. As a 'Star Priestess' (the name for the rare leaders with near-godly powers of telekinesis), she is required to remove all forms of bias from her interactions with others. She was trained (brainwashed really) almost from birth for this purpose. While she is often playful and loves to make jokes, she is bound by psychological chains to her duty. Moreover, she has a mass of complexes born from her inherent distance from the rest of humanity. Her route is made incredibly hilarious by the cycle of Shiranui making an inappropriate comment>Kazuna flushing while blowing him away>Shiranui apologizing in a way that makes it worse.
Rydia is adorable. Seriously, if you don't instantly think this when you see her leaping toward Shiranui or Shizuku, you probably aren't an otaku. She is also very charismatic in other senses, a warleader with a talent for situational awareness and tactics. Her great complex, about her mostly mechanical body, is one I can't really empathize with (I dream of discarding this fleshy body for a nice android shell), but the emotions behind it make perfect sense in a setting where machines automatically equal the enemy. The contrast between her and Hekatoncheir in her path is interesting, not the least how it ends in the threesome ending with Aqua, where Hekatoncheir finally gains something close to humanity... as he dies.
Aqua is a side-heroine available in Rydia's path as part of a threesome ending with her. She is an Earth Seed, a type of human born with a psychic connection to the spirit of humanity's homeworld. As such, her emotions are extremely limited, and she is bound to obey a creed of putting humanity first in all things. However, her emotions toward Rydia are pretty obvious from the outside (protectiveness, love, etc), and she is incredibly cute when she ceases to be an Earth Seed and has to confront the full set of human emotions.
Shizuku is... Shiranui's greatest friend (whereas Kou was his best male friend), his comrade in arms, and the person outside of Kokoro who understood him the best. As such, in her path, the relationship shift is a bit painful for both of them, since they subconsciously avoided forming such a relationship for years. She loves anything Japanese, loves fighting, and has a thing for jidaigeki. She is also Shiranui's designated tsukkomi role, meaning she spends an inordinate amount of time hitting him with a paper fan. She is an all-around genius, capable of mastering just about any skill given time, and because of this, Shiranui has a minor complex toward her. At the same time, she has a similar complex toward his ability to keep moving forward regardless of the circumstances. Typical of the 'true' heroine of any Higashide game, she is so close to Shiranui and understands him so well that they rarely require words.