These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Black Lagoon
Arc Fatigue: The El Baile de la Muerte arc. It lasted three and a half years and was comprised of so many plans that even fans were getting confused and frustrated at the end. Even the author admitted the arc was dragging.
Revy seems to have good taste in pump-up music, putting ''Peach Headz Addiction'' into her walkman before taking down Luac and his crew, and blasting "Guitar Wolf" on the radio while Rock is driving her and Ginji to the Bowling Alley where Chaka and his men have holed up.
Alternative Character Interpretation: Just who is Eda, really? Is she a goofy, so-called nun who only occasionally who takes her job as a CIA agent seriously? Or is she really a cold, domineering mastermind whose appearance to others is merely a convincing deception? Whatever it is, she's definitely not who she appears to be.
Yukio Washimine. While she's undeniably a Broken Bird for all the suffering she had to endure as the heiress to a yakuza clan, some consider her to be a Straw Nihilist who justified her unwilling (or possibly willing) ascension to the clan's leadership through a flawed interpretation of fatalism. She was in fact, given every opportunity to absolve herself of the responsibility, but couldn't see beyond her own choices because she kept putting Honor Before Reason first. Some people think that her outlook on life makes her character realistically flawed but interesting, while others see it as an irritating excuse to sympathize with a Wangsty teenage girl.
The final episode of the "Roberta's Blood Trail" OVA. There was one significant detail about it that was different from the manga: in the OVA, Roberta is nearly killed by the U.S. special forces and returns to Venezuela as a wheelchair-bound cripple. In the manga, she was not injured at all. This, as well as showing Revy getting raped when she was still in New York caused quite a bit of dissatisfaction.
The OVA also did not animate two key scenes from this arc in the manga: namely, Major Caxton realizing and sharing with Rock his suspicions that Dutch may be a Phony Veteran, and secondly, the final chat between Rock & Chang on the dock after all was said and done, leading many to question why such important parts were omitted.
Complete Monster: Chaka from the "Fujiyama Gangster Paradise" arc. A Yakuza lieutenant with a penchant for Domestic Abuse, Chaka makes his entrance beating up Rock in an effort to impress Revy. When the battle between the Yakuza and the Russian mob goes badly for the Yakuza, Chaka kidnaps and brutalises Yukio, his boss's teenage daughter, beating her bloody, and planning to sell her to a sexual sadist as part of his plan to take control of the remnants of the Yakuza. When Revy and Ginji arrive to bail her out, Chaka shoots through his own men to try and get at them, kills another man for daring to try and run away, then runs away himself, leaving his men to be massacred. Childish, stupid, and completely out of his depth, Chaka manages to make an impression only through his complete lack of conscience, loyalty, or human decency.
LHD cars in Thailand since it has a RHD vehicle policy, although it can be justified that the Thai government may have treated Roanapur as a port city that they allow LHD vehicles as long as it's used only in the city.
Some of Hotel Moscow's small arms like the MP-443 Grach, which was only developed in the early 2000s.
Boris' mention of Romanian troops in Afghanistan during the 1979 Soviet-Afghan War. Romania did not support the Soviet occupation nor did they provide troops as they condemned the invasion alongside North Korea against the USSR and its Communist allies, unless the manga/anime is playing on Alternate History.
Darkness-Induced Audience Apathy: Especially in the earlier stages, although not as much in the anime. It's still very easy to not care about what happens to anyone since they're all jerks, evil or psychotic.
Roberta. It's not hard to see why as the moment she shows up in Roanapur the body count skyrockets. This in a town where murder is only a crime if you haven't paid off the police chief or are interrupting his golf game.
Hansel and Gretel have a decent fanbase despite only appearing in three episodes.
Sawyer The Cleaner is a goth body disposal expert with a throat scar, voice synthesizer and a huge freaking chainsaw. She only appears in one arc in the anime but it's pretty obvious why she's become so popular with the fans.
Foe Yay: For rival crime lords who have attempted to murder one another at least once, Mr. Chang and Ms. Balalaika sure do behave rather flirtatiously towards each other. One scene from the manga has both of them explicitly state that the times they'd tried to kill one another are the most valued experiences that either of them posses.
Black Lagoon can be said to be made of these, containing varying references to languages, firearms, music (From Rob Zombie to Creedence Clearwater Revival) and quite a few about Westerns like The Wild Bunch (one of the characters in which was called "Dutch"...). It also contains a surprising amount of philosophy; themes such as Sartre's existensialism, consequence ethics, nihilism, phenomenalism, and Kierkegaard's "knight of faith" are openly discussed by characters (if not using those exact words).
As an example, take the firefight in the Yellow Flag which serves as Fabiola's introduction. Halfway through the fight, she throws away her right-hand handgun and breaks out a China Lake 40mm grenade launcher, an exotic weapon which even the denizens of Roanapur don't recognize (witness Revy's reaction). A little research shows that the China Lake holds a maximum of four grenades, and Fabiola doesn't seem to have any spare grenades at hand (or any time to load them, for that matter). Alert readers will notice that Fabiola launches all four grenades during the fight. When she cocks the launcher again to threaten Gustavo, she's bluffing - she's out of ammo. It partly explains why she needs a stiff drink, and why her knees give out a little later.
In Chapter 80, Major General Liu tells Colonel Ma that he had gotten an official inquiry from "14th Chang'An Avenue." This street is where many major Chinese government offices are located, and is right next to Tian'anmen Square. It would be the equivalent of saying "I just got a call from 10 Downing Street" in the U.K. or "the White House" in the U.S.
The "Goat, Jihad, & Rock n' Roll" arc dealt with Palestinian terrorists whose leader's son was killed by an Israeli airstrike. In the manga, they were even namedropped as being part of Hezbollah. These episodes aired in June 2006. One month later, Israel and Hezbollah went to war.
Iron Woobie: Rock. He has been taken hostage, abandoned by his company, captured, shot at by friend and foe alike, berated, beaten, punched and just generally abused. Despite all this, he's managed to destroy a chopper by ramming it in midair with a torpedo, call out Revy when he gets tired of her abuse, and earn the respect of Balalaika. And that's just the first couple of episodes/chapters.
Jerkass Woobie: Hansel & Gretel, Revy, Balalaika, Ibraha from the "Lock and Load Revolution" arc, and Roberta especially during the "El Baile De La Muerte" arc.
Narm: Potentially lapses into this whenever Revy decides to go on a philosophical rant. But of course, this is really just meant to show how pathetic and broken she's become as a result of a very rotten life. Her words ring hollow to the viewers because she's become hollow and is simply justifying her own way of doing things. Rock, naturally, tries to set her straight. Seems to work as she eventually stops ranting so much.
The Scrappy: Chaka made number one on a poll of "worst characters" in the manga. Yukio was also on this list, though she's more of a Base Breaker.
The English Dub is one of the best dubs out there, and one of the very best to come from The Ocean Group. It's telling that in direct contrast to most other anime, the vast majority of clips from this show found on the internet are from the English Dub as opposed to the original Japanese. Brad Swaile and Maryke Hendrikse are perfect in their roles as Rock and Revy, and Tabitha St. Germain is pants-shitting terrifying as Roberta, especially in Roberta's Blood Trail.
Hansel and his confrontation with Balalaika. He sees her sitting at a fountain, alone, and it doesn't even occur to him that she might have a sniper team watching him from a rooftop.Lampshaded when she acknowledges that there was absolutely no way that anyone who wasn't completely insane and mindlessly bloodthirsty would fall for such a painfully obvious trap.
Chaka in the Japan arc. He KNOWS that Revy's a gunslinger, from a town renowned for its toughness all over Asia...so, to attract her attention, he abuses and mistreats the man she's protecting, hoping to get her to draw her gun (in fact, Chaka only survives past his first appearance because Revy didn't have her guns with her at the time). Not to mention his treatment of Yukio, who has a badass protector of her own in Ginji Matsuzaki.