Balalaika is the boss of Hotel Moscow. It is revealed in the novel that her real name is Sofiya Pavlovena, though this name is never used in her presence. She is sometimes referred as Vladilena reduction from Vladimir Ilich Lenin. She was brought up by her grandfather, the military head of the USSR. 

Before joining the mafia, Balalaika was a captain in the Soviet Army and a Vozdushno-Desantnye Vojska paratrooper who served in the Soviet war in Afghanistan. A fine marksman and sniper, she was nicknamed "balalaika", one of Soviet Army's slang terms for the Dragunov sniper rifle. Due to Balalaika's leadership during the hellish fighting in Afghanistan, her men look up to her as their superior and will do just about anything upon her orders. As a combat officer, she is a skilled strategist and well-rounded fighter, capable of taking care of herself despite the fact that all of her troopers, including Boris, often worry about her. Although she has shown herself to be rather cynical on occasion, she is also a pragmatic and professional businesswoman. She frequently employs Dutch and the Lagoon Company, apparently because they share a mutual respect.  

Balalaika can be easily identified by the burn marks which scar most of the right side of her face, neck, and chest which she suffered in Afghanistan, earning her the nickname "Fry-Face" by those who dislike her. She has long blonde hair, and usually wears a military greatcoat, thrown over a low-cut business suit. She smokes cigars, in contrast with the other characters who smoke cigarettes. 

Based on her service in Afghanistan and the missed opportunity to participate in the 1984 Summer Olympics in Los Angeles, she is between 31–35 years old. She is one of the few people to earn Revy's respect. In turn, Balalaika also seems to hold Rock in high regard, sometimes relying on his knowledge and business skills. 

In critical operations, Balalaika calls upon a personal cadre of ex-Soviet airborne troops and Spetsnaz commandos who are Afghanistan veterans. Known as the Desantniki, they act as Hotel Moscow's special ops team. When conducting foreign operations from Thai soil, she uses the Russian cargo ship Maria Zeleska as a legal cover from the police and various law enforcement agencies. In spite of the fact that Balalaika is on the Interpol list, she uses her real name in Japan, being covered by diplomatic immunity.  Benny revealed to Rock that Balalaika's men have enough training to start and win World War III if they wanted to. They were all Afghan Veterans with insane amount of training and skill. With Balalaika as the brains for their operation, her men became unstoppable killing machines.  

Okajima Rokuro is a Japanese businessman in a town full of Japanese businessmen. His normal day consists of social drinking with clients and being kicked around by his bosses. He finally gets a break though, as he's sent by his company to the tropical seas of Eastern China to deliver a disc. But his boat gets hijacked by a band of mercenaries hired to retrieve the disc. Rock (as he is newly dubbed by his captors) catches the interest of the only female merc Revy as she thinks he's worth a ransom, taking him hostage. However, the disc that was stolen has a terrible secret that's unknown to Rock, which causes massive confusion and chaos for both him and his kidnappers.

Okajima Rokuro - now known almost exclusively as 'Rock' - was once a typical, put-upon Japanese businessman. Then, on a routine business trip, he was kidnapped and ransomed by the Lagoon Company: a band of mercenary pirates operating out of the crime-riddled city of Roanapur. Abandoned by his bosses, he joined the Lagoon Company. Now he must try and stay afloat amongst the ever-shifting politics of the criminal underworld, while simultaneously avoiding death at the hands of his quick-tempered, gun-toting co-worker, 'Two Hand' Revy.
 
(Source: Anime News Network)

Roberta, the terrorist-turned-maid that made her appearence in the first season of 'Black Lagoon', returns in this five-episode OVA series - and this time, all bets are off! 
Roberta's benefactor, the patriarch of the Lovelace clan, is murdered during a political rally. The assassin's trail soon leads back to Roanapur - so now she has returned on a mission of vengeance! However, close behind her is the new patriarch, Garcia, as well as Roberta's apprentice (and maid), Fabiola Iglesias. As the body count of Roberta's bloody rampage mounts, forces from within the corrupt island (which includes the Lagoon Company), as well as overseas converge on what threatens to escalate into all-out war!

Rokurō Okajima is just an average Japanese salaryman, living an average life. But when he's taken hostage by the crew of the Black Lagoon, Rokurō finds himself thrown headfirst into a deadly world of outlawed heroes, brutal villains, and blazing gunfights. Where he ends up is anyone's guess, but one thing is for certain—he's in for a wild ride!
 
(Source: Viz Media)

Tankathlon is a new form of tank sport gaining slowly gaining popularity among Senshado enthusiasts. While also involving tank battles, Tankathlon is distinguished by its lack of official oversight allowing any school with tanks to participate in a battle anywhere at any time, and a 10-ton weight restriction on tanks used, limiting battles to light tanks and tankettes.

Special omake episodes from the Blu-Ray releases, showing the heroines and foes in funny, uncommon situations.

Rock (Okajima Rokuro) was just a normal Japanese businessman, but through a series of unlikely events, he found himself part of the "Lagoon Company," a group of transporters who do a little pirating on the side. Together with Dutch, Revy, and Benny, he sails the seas of Asia aboard the modified torpedo boat "Black Lagoon." 
Their base, the lawless city of Roanapur, is just barely balanced on the brink of outright war, controlled and occupied by criminal organizations from across the globe. Standing above the rest are Balalaika of Russia and Chang of Hong Kong. 
Our story finds Roanapur just a little while before Rock, with Revy in tow, is due to head back to his old home of Japan. 
It is a tale about soldiers who once fought united under a cause in a land of sandy winds, the strictly personal reunion of a captain and her one-time subordinate...