The year is 2020 A.D., and the once-peaceful city of Tokyo is now a crime-infested wasteland. Kozuki Tsukasa — who was raised as a boy by her police parents to avoid being the victim of the shockingly common crime of sexual assault — has been thrown out on the streets with her three brothers in the aftermath of her parents' death in an internal dispute of a Yakuza clan. In order to feed her family, she decides to scam a rich classmate whose father was also killed in the dispute by promising information on the murderer in exchange for a high-class meal. The classmate, however, turns out to be none other than Shirogami Ryuji, heir to Kuryugumi, the largest crime syndicate in the Kanto region — and he doesn't take kindly to being fooled. Upon discovering Tsukasa's lies, he saddles her family with an enormous debt in order to pay for the food they ate, forcing Tsukasa to work as a bodyguard in order to pay it off.
Tokyo Crazy Paradise employs the following tropes:
- A-Cup Angst: Asago. Sadly, her small chest is not her only source of insecurity.
- Age-Gap Romance: With an even ten-year age difference, Asago and Munakata are this.
- And I Must Scream: Display cases that keep real people Including, briefly, Tsukasa alive and paralyzed as "living art" (e.g., Sandro Botticelli's The Birth of Venus). Overlaps with Hand-or-Object Underwear and Godiva Hair, also taken from the original.
- Artificial Limbs: Asago gets an arm sliced off and opts to get a prosthesis instead of reattaching the limb in order to minimize rehabilitation time.
- Attack Animal: Garyukai's drugged civilians act as attack animals.
- Battle Aura: When Tsukasa gets serious, she radiates terror. Apparently she gets this from her biological mother, Wakasa.
- Beach Episode: when Tsukasa is suffering from the side-effects of a poisoned bullet, she develops a super-sweet and childish personality and demands to go to the beach. Ryuji decides to take her alternate Femme Fatale personality.
- Brick Joke: The author states in notes to volume 4 that Azumi is supposed to look like a male transvestite. Ryuji has a strong resemblance to her when he is forced to disguise himself in drag in volume 13.
- Conveniently an Orphan: The fact that both Tsukasa and Ryuji are orphans allows them to embark on whatever crazy Yakuza adventure they want.
- The Don: Shirogami acts as a don when conducting business.
- Faux Action Girl: For all her bluster, Azumi faints at the sound of gunfire.
- Girls with Guns: One of the main reasons Asago was chosen as Ryuji's fiancée was because of her proficiency with a firearm.
- Gladiator Games: Tsukasa crashed an illegal gambling ring in which female fighters with massive amounts of debt were given a drug to make blood look like money, then forced to fight to the death.
- Good Cop/Bad Cop: Akira and Munakata — while Akira is interested in reforming criminals, Munakata just wants to kill them in as brutal a manner as possible.
- I Just Want to Be Badass: Asago, so very much. She's pretty good with a gun, but that doesn't help much against Psycho Serum-fueled monsters. Unlike some other examples, she gets her wish.
- It's All My Fault: Asago has a moment like this when Ryuji is put in a coma by jumping in front of a bullet meant for her.
- Love Triangle: Akira and Ryuji both love Tsukasa, who remains oblivious despite rather obvious displays of affection from both sides.
- Luke, I Am Your Father: In a bizarre twist of fate, Tsukasa, sworn enemy of most Yakuza, is the daughter of Wakasa, the iconic second wife of a once-powerful syndicate.
- Mafia Princess: Asago is a yakuza princess.
- No New Fashions in the Future: Despite taking place in 2020 A.D., everybody dresses like it's still 1997.
Accidentally averted when a flashback to the year 2011 shows Wakasa wearing skinny jeans, which were back in style by that point. - Pin-Pulling Teeth: Ryuji does this on his way to rescuing Asago and Tsukasa in volume three. While driving and (unintentionally) blasting strangely appropriate enka.
- The Pirates Who Don't Do Anything: Kuryugumi doesn't deal drugs, kidnap, demand ransoms, participate in human trafficking, gamble illegally, or manage prostitution rings. One wonders what exactly it is they do that makes them the largest syndicate in Tokyo...
- Prince Charming Wannabe: Asago is constantly followed by one particular creep when she is at school; he showers her in roses and gifts whenever he can. She responds appropriately by beating the shit out of him.
- Promotion to Parent: Takuma drops out of high school and gets a job at a casino to provide for the rest of the Kozuki siblings after their parents' death.
- Recursive Crossdressing: Tsukasa does this on many an occasion — because very few people know that she is a girl, she disguises herself as a female when undercover (often complaining that she feels like a transvestite when she does so).
- The Rival: Asago and Tsukasa are rivals.
- Shame If Something Happened: Asago, in an attempt to separate Ryuji and Tsukasa, reminds the protagonist that her brothers happen to work in a very... dangerous part of Tokyo. Demonstrated when one of them is shot in the leg on the way home from work one day — ostensibly as a warning.
- Shipper on Deck: Kamojima and Bun-san are fervent shippers for Ryuji and Tsukasa.
- Smoking Is Cool: Ryuji smokes like a chimney, despite being only fourteen. This only serves to further the respect he gains from his underlings.
- Sweet Polly Oliver: Tsukasa was raised as a boy to prevent her from being a target for assault and to keep her resemblance to Wakasa to a minimum.
- Those Two Guys: Kamojima and Bun-san, Ryuji's two underlings who look more like salarymen than Yakuza most of the time.
- Variable-Length Chain: Tsukasa's usual weapon is a chain with conveniently varying length.
- Vice City: Tokyo and pretty much any big city in Japan is completely crime-riddled.
