The character "Ryuu" means "dragon" in Japanese, and as such, its use as a name or part of a name in Japanese media [[MeaningfulName tends to have meaning]]. But even more interestingly, throughout the years, a certain archetype has formed around the name. Characters named Ryuu or who have the syllable Ryuu in their name have many of the following character traits in common:
* Male.
* Usually the protagonist of their work, or at least an important secondary character.
* They're pretty much universally good guys.
* They tend to be young, between mid-teens and late 20s. If they are older than that, they usually didn't start that way in the series, instead having grown older as the series went along. If older than that, they tend to be mentors or father figures.
* They tend to be good fighters, if not the best in their series, but they might not start that way, growing into it as the series moves along.
* They have outgoing personalities, if not downright HotBlooded.
* They '''HATE''' injustice with a passion. Even if they're not actively heroes, seeing some kind of injustice committed before them is a surefire BerserkButton. A an extension of this attitude is that they usually have PapaWolf and WifeBasherBasher tendencies: it is ''not'' a good idea to hurt a kid or a woman in front of a character named Ryuu.
* They usually suffer in full of TheDulcineaEffect. If a woman is in trouble in front of a character named Ryuu, he WILL jump in to protect her, no matter who she is. If the woman's a bad girl, this action might even make her change her ways.
* They tend to have a [[TheRival rivalry]] with another character. The rival, to fit the pattern, tends to be associated with [[TigerVersusDragon the tiger]].

Do keep in mind that this is not universal (for example, Ryuu Soma of ''ArgentoSoma'' is quite a dark and nihilistic character), but it is common enough that it's become a pretty well recognized phenomenon. Also, the character Ryuu can be replaced by the word Tatsu(the character for Dragon in the Eastern Zodiac), while still having the characteristics of this type of character. The character Ryou is also frequently used to similar effect.

The correct pronunciation is difficult for anyone who isn't a native Japanese speaker -- the "r" is actually a sound halfway between r and l, with a "pop" at the end. Pronouncing it "Dyoo" is a close approximation -- it would sound a little off to a native speaker, but not as much as "Ree-oo". "Rye-oo" should only be used if [[Manga/YakitateJapan you are already bread]].

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!!Examples:
* Ryuu from ''StreetFighter''. His rival is Sagat, who's associated with the tiger.
** Although the kanji used to spell Ryu's name in promotional materials for the original ''VideoGame/StreetFighter'' stood for "prosperity", not "dragon".
* Ryuu, Raoh's son from ''FistOfTheNorthStar''.
* Ryuuhaku Todou of ''VideoGame/ArtOfFighting / VideoGame/TheKingOfFighters''.
** Technically, the main protagonist in that series is ''Ryo'', who is associated with the tiger. In an odd subversion, his lifelong pal and training partner, Robert Garcia is the one associated with the dragon, but he's the [[RyuuAndKen "Ken"]] of the series...
*** Also, Ryuuhaku Todoh has never been a playable character in ''VideoGame/TheKingOfFighters'', though he was playable in ''VideoGame/CapcomVsSNK2MarkOfTheMillennium'' and his daughter has been a playable character in KOF from time to time...
* Kazuma Kiryuu from ''VideoGame/RyuGaGotoku''. In a subversion, though, his rival in the second game is Ryuuji Goda, another dragon-themed character(although he's more a NobleDemon than a full-blown bad guy, and he still exhibits many traits associated with his name).
* Ryuu from ''BreathOfFire''. Many of his companions are tiger-themed to contrast with him, and, well, he's a ''literal'' dragon.
* The -Ryuu robots from ''GaoGaiGar''.
* Ryou Saeba of ''CityHunter''. His lechery makes him kind of a weird fit, but he definitely fulfills this trope.
* Ryouma Nagare of ''GetterRobo''.
* Ryuudo from ''{{Grandia II}}''.
* Ryuu Hayabusa from ''VideoGame/NinjaGaiden''.
* Dragon Shiryuu from ''SaintSeiya'', except maybe for the personality part. Also counts for his son Ryuuhou from ''SaintSeiyaOmega''.
** Yes, Shiryuu is much calmer and collected than his fellow Bronze Saints. No, it does not stop him from being hot-blooded as all hell.
* [[VideoGame/{{Strider}} Strider Hiryu]].
* Ryuuichi Naruhodo, AKA PhoenixWright. In the third game, he actually gets impersonated and threatened by a gangster named Furio Tigre, aka The Tiger (Toranosuke Shibakuzo, aka Zenitora), who's obviously associated with tigers.
** The only element of this trope that doesn't really fit Phoenix is "good at fighting". However, he is a playable character in ''Ultimate MarvelVsCapcom3'', even though he can't fight worth beans in his own series.
*** He's not that great in [=UMVC3=] either... But then again, what did you expect putting a lawyer in the fighting arena with superheroes, supervillians, gods, trained martial artists [[MyFriendsAndZoidberg and Wesker]]?
*** [[LethalJokeCharacter If you know what you're doing, he's quite the]] {{Badass}}.
* ''KamenRiderRyuki'' as well as Ryu Terui from ''KamenRiderDouble''.
* Ryuuji Takasu from ''LightNovel/{{Toradora}}!'', in which the whole premise of the title involves the concept of Tigers and Dragon's in Eastern Culture being seen as counterparts. 'Tora' is the Japanese word for tiger, while 'Dora' comes from 'Doragon' the japanese pronunciation of the English word 'Dragon'. The characters names in the show are the reverse of the title, Ryuji's name deriving from Ryu, the Japanese word for dragon, and the female protagonist/love interest is named Taiga Aisaka, 'Taiga' being the Japanese pronunciation of the English word 'Tiger'.
* While not their proper names (being their hero names instead), the three protagonists of ''MadanSenkiRyukendo'' fit the bill.
* Ryuu Tendou from ''ChoujinSentaiJetman''. A non-Red example can be seen in Ryuu Hoshikawa in ''KagakuSentaiDynaman'' or to a smaller extent, Ryuunosuke Ikenami from ''SamuraiSentaiShinkenger'' and Ryuji Iwasaki from ''Series/TokumeiSentaiGobusters''. Then there's the [=RyuuRanger=], Ryou of the Heaven Fire Star from ''GoseiSentaiDairanger'', another Red ''and'' dragon-themed.
* Michael (known as Ryuuto in Japanese) of ''VideoGame/PokemonXDGaleOfDarkness'' is a subversion; the proper translation is "to kill".
* ''PeacemakerKurogane'' has Ichimura Tatsunosuke (where "Tatsu" is the character for the EasternZodiac sign of the dragon) and the HistoricalDomainCharacter Sakamoto Ryoma, whose name is written with the characters for "dragon" and "horse", and who fits the trope quite well.
* Ryuuzaki (one of the aliases of HeroAntagonist L) from ''Manga/DeathNote'' fits all the requirements except the "outgoing personality" bit (and according to WordOfGod his alignment is questionable) but he's a good fighter, trained in {{Capoeira}}, he hates injustice with a passion, and has a rivalry with Light/Kira of the obvious RedOniBlueOni type. There's also the {{Shinigami}} Ryuk and [[spoiler: the OTHER Ryuuzaki]] from ''LightNovel/AnotherNote'' but they are subversions, one being an amoral monster and the other a [[spoiler: SerialKiller]].
* Ryuuma from Eiichiro Oda's one-shot ''Monsters'' fits all requirements to some degree. His later appearance in ''Manga/OnePiece'' - not so much. [[JustifiedTrope Justified]] in that he got [[DirtyOldMan Brook's]] personality and is revived as an [[OurZombiesAreDifferent evil zombie]].
* Ryuuta Ippongi from ''OsuTatakaeOuendan'' fits this almost perfectly.
* Ryugamine Mikado from Durarara!!, minus the outgoing personality and fighting skills (although he started working on that in the light novels).
* "Wooden Sword" Ryuu of ''ShamanKing'', having all but a clear rivalry with a tiger themed character. Instead, his partner spirit has (or, ''[[HeelFaceTurn had]]'') a rivalry with the main character's partner.
* Ryuuji Kisaragi of ''LightNovel/DragonCrisis''.
* In ''MobileSuitGundam'', we have Ryu Jose. Though he's not the protagonist, he is the most skilled pilot of the crew in the beginning, is the most likeable, big brother type, and [[spoiler: [[HeroicSacrifice sacrifices]] himself to save his crew. His death is a large reason that the crew shape up and start working together better.]]
** In ''GundamSentinel'', the protagonist's name is Ryu Roots.
* Kusuha Mizuha and Brooklyn "Bullet" Luckfield of the ''SuperRobotWarsAlpha'' timeline are considered the mains of the series. Their ultimate robot? [=RyuuKoOu=].
* Ryuuichi and Ryuuji, recurring antagonists from the ''VideoGame/KunioKun'' series. Their names can be read as "dragon one" and "dragon two," and they are indeed {{Expy}}s of the ''VideoGame/DoubleDragon'' protagonists (though their DubNameChange in ''VideoGame/RiverCityRansom'' somewhat obscured this). Toraichi and Toraji are presumably their "tiger" counterparts, but they never appeared in the same game.
* Tatsumaru, Rikimaru's brother in the ''{{Tenchu}}'' series.
* A somewhat ambiguous case, but [[AntiHero Ryuuho Tairen]] of ''{{sCRYed}}'' is nominally one of the protagonists of the series, along with Kazuma. His father Ryuu is a pretty decent guy, too.
* Ironically subverted with ''Gatchaman''. While there ''IS'' a Ryu on their team, he's the BigGuy. And the person who fits the model of being the "Ryu" of that team (protagonist dressed in white) is actually named ''Ken''. And [[TheLancer the "Ken"]] of the team is named Joe.
* Ryu from ''Chojin Sentai Jetman''.
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