Angst? What Angst?: Kouya. For someone who is having trouble with his family, he does a good job hiding it in everyone else's routes. He doesn't really show his angst about the ordeal until his mother visits his apartment and leaves a note.
RPG, it only plays in a few scenes, such as when Hiroyuki and Shun visit Gaku, and yet it's somber guitar, followed by some fast-paced rock energy, makes it fit for someone like a final boss.
free0352 the trailer music. It's mix of happy and tragic beats leaves for a good introduction to the game that many fans considered it the main theme of the game.
piano3_001, the title theme. A beautiful piano piece that perfectly encapsulates the feeling of returning home and seeing your friends again after so long.
Kounosuke is usually considered to be the weakest of the nine guys, due to his unpopular route and some finding his antics to be rather unamusing. That being said, he does have a couple of fans who like him, whether they find him cute, funny, or because he is genuinely nice towards Hiroyuki.
Kouya is loved by the fandom for his attractive design and calm and caring behavior towards Hiroyuki. On the other hand, he also has detractors that found his route and character to be rather generic, in comparison to the more colorful cast.
Shun has fans that find him to be adorable and find his relationship towards his family and their tradition to be rather tragic. However, there are others who find his route difficult to get through because he acts like a little kid, making the love scene hard to sit through.
Big-Lipped Alligator Moment: During Tatsuki's route, while you and Tatsuki go to help set up for the summer festival. Hiroyuki and Tatsuki end up rushing to the bathroom after eating expired manju. Botan turns out to be in one of the stalls, out of toilet paper. If you pick the option to help him by giving him an empty roll, a giant Chuukichi starts attacking the village. Hiroyuki is given a weapon to stop him. Not only that, it gets weirder. Hiroyuki, right out of nowhere, turns straight, attracted to human girls, and the whole story turns into a typical weekly Shounen manga. Naturally, it's lampshaded in the segment you get afterwards where Shigure and Chuukichi tell you what you did wrong. Afterwards, you end up having to restart the day and no one speaks of it again.
Epileptic Trees: Kyouji has Eyes Always Shut, so there has been some debate over whether he will turn out to be evil. Perhaps people watch too much Bleach? This isn't really helped by how Kyouji never stops smiling, while being out-right evil is not likely the case, Kyouji is very possibly a Stepford Smiler.
Tappei has proven to be rather popular, easily having more fan-art (specially of the NSFW variety) than some of the nine guys.
Ten Kodori. Once he was introduced he proceeded to become very popular for his badass design and his behavior. He also is quite liked for being one of Shun's nicer relatives, vowing to protect him, and for being a Friendly Rival to Juuichi.
There are a lot of theories floating around about some characters about whom not much has been officially revealed. One particularly popular interpretation of Torahiko is murderous Yandere. To explain, Torahiko is the only character so far who displays overt affection for Hiroyuki. The fans have jokingly exaggerated his obvious interest into a Fatal Attraction-esque obsession. It also helps that the game takes place in a small, homely, peaceful village in Japan during the summer, remind you of anything...?
Some fans jokingly suggest than the D in the D-Get patch on Torahiko stands for Dick-Get.
Memetic Loser: Torahiko was heavily showcased as being the main choice for Hiroyuki and was saved to be the last character released. Unfortunately, once the original game was cancelled, many fans have poked fun at the poor tiger for having no route despite being the intended main love interest. In comparison, Kyouji and Soutarou have mostly escaped this on account of actually being love interests for each other.
For instance, some of the characters like Torahiko have no sex endings so far, yet there is so much Rule 34Fan Art of them.
On the Bara Boards (Not Safe for Work), there has sprouted a meme of taking Morenatsu character graphics and adding text to them, à la LOLCats.
Some of Hiroyuki's ridiculous goofyness has become the subject of humor, an infamous example being the "Is that a piano?" bit from Kouya's route, during a scene in which Hiro hears him playing guitar in a forest.
The interpretation of Kyouji having a hidden dark side beneath his nice guy persona is becoming rather popular in certain boards, attributing Kyouji traits of a rapist and murderer with Soutarou being his main victim, this Kyouji is known as Rapist!Kyouji and has been for some reason compared with Adachi from Persona 4.
When he's not being a Memetic Loser, Torahiko tends to be depicted as an Ax-CrazyYandere who would do anything to keep Hiroyuki to himself.
Moral Event Horizon: Hiroyuki's rape of Shin and Juuichi in their worst possible endings to their routes.
One True Pairing: Kyouji and Soutarou, thanks to their senpai/kohai relationship with each other and becoming a couple in Juuichi's route. Even when the game ceased development and cancelled their routes, most fans found these two to be a cute pairing, and are happy to see them together.
The Scrappy: Hiroyuki. Some people don't like him due to the writing inconsistencies, the fact that he can potentially rape two husbandos that you're trying to romance, Juuichi and Shin, if you pick the wrong choices or simply because he's human.
Viewer Species Confusion: While Kouya and Mitsuhisa are officially huskies, many fans have mistaken the two for wolves thanks to their grey fur and golden eyes. It doesn't help that Kouya is bigger than the actual wolf Shun, whose design is based on the smaller Hokkaido Wolves.
Shin, despite his cold demeanor, is seen as far more tragic by many fans. He is an ill boy who moved to Minasato after a serious asthma attack. Unfortunately, due to work-related reasons, his parents hardly visit him after the situation, making Amaki his closest friend and relative. His asthma has also made it hard for him to participate in many activities, thus making him seem more aloof. He also finds himself falling for Hiroyuki, something he gets really troubled by, even trying to force Hiroyuki out of his life and begging him to hate the poor cat, and it can go south, really badly if the Worst Ending is chosen.
Torahiko, despite being the one to invite Hiroyuki to Minasato, can become one if he isn't the character you chose to date, which now always happens thanks to the game's cancellation. For a specific example, he confesses his feelings for Hiroyuki on the former's birthday, even visiting his house. Unfortunately, because this only happens in Juuichi's Route, Hiroyuki has to reject Tora in order to continue.
Shun Kodori could REALLY use a hug, especially when he starts crying. Being called a shameful heir to the Kodori Clan, by his own grandfather no less, certainly didn't help the poor wolf. There's also the fact that he's been waiting for Hiroyuki for 5 years to return.
, it only plays in a few scenes, such as when Hiroyuki and Shun visit Gaku, and yet it's somber guitar, followed by some fast-paced rock energy, makes it fit for someone like a final boss.