I've been re-re-rereading this series for over half a decade & decided to re-re-rewrite the review, after Old Xian added a huge new plot element & also after reading several Korean & Chinese BL webtoons.
First let me say that things gay boys tend to find annoying about Japanese BL tend to not be present in Korean & Chinese works. I have to recommend them to our Fudanshi bretherin. All of the boys are appropriately masculine for their age, there's no forced sexual tension, no stupid misunderstandings that could easily be fixed by conversation, no jealousy melodrama, no one is "the chick" in the relationship, there is no canonically clearly established seme-uke dynamic between Jian Yi & Zhan Zheng-Xi, there's a heavy emphasis on bromance, there will be no romance until the boys are at least college aged, & they've been in Jr. high for the past 6 years. He Tian is working on getting his love interest to even acknowledge him as a friend after having bullied him in school.
19 Days is a series that has gotten its author Old Xian awards. She's a top tier webtoon blogger with just under 10 million fans on Weibo alone, who likes to stay in-character as her male counterpart from her Mosspaca series online & at conventions (she should invest in a blonde wig for the Cons).
This series' humble beginning started with a one-shot in 2013 in an anthology series by the same name. For a couple of years, the series was a simple 4koma gag series. Then around chapter 100, the art started getting more detailed & readers were suddenly graced with plot elements, character development, & a couple of seemingly minor cast members became secondary protagonists & regulars. It went from a plotless comedy to a dramatic coming-of-age tale about 4 middle school boys' journey to becoming men. The romance is actually secondary & is a realistic slow-burn, making it popular with the same expanded audiences as Yuri on Ice.
Most items the students wear is Mosspaca brand, tying them to the Mosspaca Advertisement Department webtoon, in which 19 Days is just a comic Old Xian works on when he's not having wacky advertisement adventures. How funny that a series completely grounded in reality is just a work of fiction in a series not grounded in reality at all.
The current story arc came about in a series of teaser images depicting the boys grown up & in a rock band that would be called One Day. Much like the over-reaching plot of Tian's mafia ties through his brother, & Yi's mysterious estranged dad who is likely either a mafioso or a politician, this will be an over-reaching plot over all arcs.
Couple 1:
Zhan, Zheng-Xi: A chill, laid-back guy who is only Tsundere around Jian Yi. He enjoys basketball, Japanese manga, & video games. He has a little sister who likes video games & looks just like him. She thinks Jian Yi is weird & doesn't want her brother hanging out with him. He is the kind of guy who never says no to anything offered for free, be it lunch or a trip to a sauna. He is constantly policing Yi's behavior in public, & while he comes off as overly wholesome, he's not above letting his friends cheat off his homework.
Jian, Yi: He is very childish, looks effeminate but is very boyish, very romantic, very optimistic, energetic one moment & lazy the next, pie-in-the-sky ambitions, & a look-before-you-leap approach to situations. He is very sassy & is usually yelling at people, but is always the first to stand up for someone else, & has never shown anger towards Zheng-Xi. He is the spitting image of his mother. He never met his father but kept his father's surname. His father is a very mysterious person who will cause him & his mother trouble. Some speculate that Yi's may be the illegitimate child of a politician, or that his father is a jailed mobster.
Yi was a crybaby. When baby Zhang-Xi met him in Kindergarten, he promised to protect him forever. In their teens, Zheng-Xi is still very defensive of him, despite frequently beating the shit out of him himself. (It's only okay when he does it). Yi develops a single-target sexuality for Xi. Xi just wants to stay best friends but can't bare to hurt Yi's feelings. Old Xian has made it very unclear which guy would be the uke & seme. Most feel that Yi is the chick in the relationship, but if you read the entire series in one day, you'll note that Yi is constantly trying to grab Xi's ass & pin him to the ground every god-given chance he gets.
Couple 2:
He, Tian: A spoiled rich chain-smoking brat, who's also the 3rd smartest honors student in his school, who lives all alone in a barely furnished condo & can't cook for shit. He's the toughest most fearless guy in school, & the most popular guy to the girls. He seems to come from Mafia stock & has a very negative & distant relationship with his family. He is potentially Bi if his reading material is any indication, but he is very openly gay & a has that Pepe le Pew/Elvira Duff issue of no sense of personal space, showing up unexpectedly, persistant following, & absolutely smothering the object of his effection to death with effection until they run screaming. He is the textbook definition of a Simp when it comes to Guanshan, & seems to take some sadomadochistic joy from it. He is the tallest & toughest guy in school & is favored by the staff & female students. So between growing up rich, having a scary mafia family, being unbullyable, & having the teachers & girls on his side, he grew up ad the kind of guy who can do whatever the heck he wants without caring how he looks or what others think about him, do he is VERY open about his sexuality, despite in a country that frowns on it.
Mo, Guan-Shan: Easily the saddest, most pitiful guy in the series. His tsundere levels are over 9,000 & even his closest friends with feel the wrath of his temper. Like Yi, he grew up mostly fatherless due to an incident that set a negative chain reaction of events that haunt him to this day. He has a skill for both cooking & getting into trouble. He comes off as a lone wolf who chooses to lead his own small pack. In his point of view, he finds himself in the company of annoying acquaintances who call themselves his friends, are always intruding upon him, taking advantage of his hospitality, & dragging him places he doesn't want to go. So he is bouncing back & forth between two sets of friends at school.
At first, Tian started as a love rival for Yi. Then for reasons only the author can fathom, he completely lost interest in him & immediately took a slow interest in the scrappy kid who had been bullying Yi. Guan-Shan absolutely detests Tian, due to their first several meetings being Tian beating the crap out of him & then sexually harassing him, & then doing both intermittently. His friends think Tian is an awesome scary badass. Currently, Tian is trying to make Mo hate him less by helping him get money to support his mother, & keeping him safe from street thugs & the OTHER school bully, but being a creature of bad habits, he keeps ruining any good will he has with Guan-Shan by dragging him off to places he doesn't want to go, showing up at his house whenever he feels like it, making him wear things he doesn't want to, following around in secret & taking pictures of him, & repeatedly violating his personal space. The journey here is we know that they'll end up together, so how does Tian win him over after shooting himself in the foot so many times?
Other notable characters:
He, Cheng: A rich & extremely intimidating man with a completely chill temperament. He appears to be a high-ranking mafioso under his father. It's never stated but heavily implied. He is about 15 years older than his baby brother Tian, whom he raised like a son, & is frequently mistaken as being his father. He seems more concerned about Tian's happiness than how well he's doing in school. He is familiar with Yi's mother & has had his henchmen guard Yi, making fans wonder what kind of connection the two mysterious fathers have with eachother.
Brother Qiu: A mafia thug with a bit of a resemblance to Guan-Shan in hair, face, & temperament. He absolutely hates kids, yet constantly finds himself "babysitting" them.
Xiao, Hui: She started off as a nameless love rival for Zhen-Xi & is kind of Yi & Xi's friend now.
She, Li: He is very much like Tian, but a true sadist with seemingly no redeeming qualities. He also seems to have the exact same taste in men as Tian, as he bounces back & forth between Yi & Guan-Shan. He doesn't seem to feel pain, enjoys provoking fights, & he has his own gang.
Facts the loudest fangirls ignore:
*These boys are about 14-15 years old right now.
*Old Xian has implied numerous times that they don't hook up until college.
*They have been in jr. high since 2014.
*Not even one year has passed in this story.
*China has strict rules on BL & a ban on porn.
*Only low profile comic artists can get away with sending X-rated scenes from comics through QR codes & phone.
*Old Xian is very high profile.
*No one in this story is ever going to fuck. Accept it.
Now I have a treat for anyone who made it this far! Tencent animated & voice acted the series. It's really low budget, but it's better than no anime, right? Of course thanks to Chinese censorship laws, all cigarettes, flipping the bird, calling people a chicken dick, & gay kissing has been left out, but they were apparently fine with keeping the underage drinking & violence. ¯_(ツ)_/¯ It also skips the first 100 chapters, going straight into when Mo Guan Shan was introduced. It also skips chapters & most of the iconic multi-chapter arcs, & even mixes chapters so that all context for what's happening is missing.
https://www.bilibili.com/bangumi/media/md12118629/