There's a reason we call the trope "Draco InLeatherPants". There's something about tanned cow hide that's cool and extremely sexy to many people.
Leather's Badass associations originally stem from leather being the garb of choice for bikers, who wore it for practical reasons. One of the quickest ways to show that someone is Badass or sexy in a "bad boy/girl" way is to dress them up in shiny black leather.
It will be black leather the vast majority of the time. Other colors just don't have the same effect in most cases, though white and red do sometimes work, as does the traditional brown. For increased badassery, have the black leather lit by a sodium lamp: Black leather, deep green highlights.
See also Spandex, Latex, or Leather, Pretty in Mink, Dominatrix, and Leather Man.
Surprisingly enough, though, it's mostly his protagonists that wear leather. Hell Kaiser Ryo in Season 2 of Yu-Gi-Oh! GX plays it straighter than most.
Tsume in Wolf's Rain appears to wear a ripped leather jacket and pants. Of course, that's just part of his disguise (look at the title again).
Naomi Misora and Mello in Death Note. Interestingly enough, Word Of God says that Mello ended up dressing like that because the artist put him in clothes that he likes drawing.
Edward Elric from Fullmetal Alchemist is never seen without his leather pants and occasionally even leather jackets. He's regularly mocked for his tacky taste and gaudy fashion sense (at least, in the manga).
Fate Testarossa of Magical Girl Lyrical Nanoha has been fighting in a leather one-piece since she was nine. Before her mother, Precia, was first shown to viewers, many of them wondered why she let her child dress like that. Turns out that, besides being the worst mom ever, she also dresses like that, and her device's most commonly used form is a whip.
Nico Robin from One Piece wore a very tight, very leather ensemble during the CP9 story, complete with grade A length, high heeled leather boots.
Kira Yamato often wear leather outfits as his civillian clothes, mainly in Gundam Seed Destiny. They are usually complex designs with zipper sleeves and other strange styles.
Archer of Fate/stay night has some amazing pants. While his breastplate is stated to be some futuristic alloy, the trousers look to be leather (that he purchased at a goth or fetish shop).
Surprising amount of characters in Gunnm/Battle Angel Alita, starting from the heroine herself and Zekka, even though they technically don't really need clothing at all, most of them being Hollywood Cyborgs. They usually wear it for its sheer Badass appeal — there's the definite correlation between the amount of leather and general badassitude of the character in the series.
And his inspiration, Batman (though just what that costume's made of varies).
Jason Todd/Red Hood wears a leather jacket most of the time.
Planetary's Jakita Wagner. Black leather body suit with red trim. And a bit on the front she leaves unzipped at all times to expose some of her cleavage.
Durham Red in Strontium Dog is certainly fond of leather.
The Raven royal family in Scion LOVE black leather.
Most of the Front Line in No Hero wear non porous leather with special masks for protection.
The Blackhawks are a classic example. Zinda Blake, aka Lady Blackhawk, continues the tradition in Birds of Prey.
Chassis Mcbain's racing suit in Chassis. It's not specified exactly what it is made of, but it certainly appears to be leather.
Wynonna Earp, especially in her originals 1990s run. Her later series expand her wardrobe slightly.
Heroic characters in The Deaths of Ian Stone generally avoid leather, but the Harvesters seem to have realized its intimidation factor. Medea in particular really works it.
Red is featured again in the Klingon dinner dress attire in Star Trek VI.
Fight Club: Tyler Durden wears red leather and goes as far as to say that in an ideal world a man will own just one set of clothes for his entire life, made of leather. He's supposed to be a subconcious representation of the repressed protagonist's idea of masculinity.
The alternate title of the 1968 British-French film The Girl on a Motorcycle is Naked Under Leather.
In the movie, Eragon and just about everyone of importance wears leather of some kind. This is extremely not accurate. Justified, though not trope-wise, in that the wardrobe production was given little time to make the vast amounts of costumes needed, and someone had bought large quanties of leather; they had to use what they had, budget wouldn't allow more costs.
Well it wasn't for logic, the elves of the series were of the "die-hard vegan, would die rather than kill an innocent bunny" variety.
Every male character in J.R Ward's Black Dagger Brotherhood wears black leather when fighting lessers.
Sherrilyn Kenyon's Dark Hunters series: Badass Army protecting the human world from things that go bump in the night.
Caine, the Badass protagonist from Heroes Die always wears black leather.
Geralt is almost never seen out of his favorite leather jacket with lots of silver trim and studs, and matching pants. Somewhat justified in that leather indeed was a material of choice for a combat wear in The Dung Ages, and silver is useful in his line of work, but we sometimes almost get to hearDandelion cringe at his friend's fashion sense.
Kate Daniels bought her black leather jacket in her teenaged "bravo" days, when she was deliberating trying to invoke this trope. Developing into a more mature, sensible adult doesn't stop her from wearing leather at every chance, though, because leather affords some protection from attacks.
In her first appearance in Time Scout, Margo Smith is wearing a nigh-heart-stopping tight leather miniskirt. A character later describes her as "doe eyed one second, hell bent for leather the next".
The Doctor's companion Fitz, from the Doctor WhoEighth Doctor Adventures, has a leather jacket. He also wears leather trousers once or twice.
Harry Dresden's distinctive, enchanted black leather duster comes up frequently in The Dresden Files, though its badassery is rarely explicitly stated. It is brought up when Harry needs clearance to enter a decidedly shifty night club, but Thomas is able to get him in because he's "A man in a black leather coat."
Buffy and Faith are both seen wearing leather pants and jackets on more than one occasion, especially Faith. Angel and Spike both go in for leather jackets.
Especially Faith. And don't forget: Spike's leather coat is one he took off the corpse of a Slayer he killed. So maybe it is standard issue clothing.
Spike and Faith prefer black leather jackets, but change to brown leather on occasions when they're trying to get in Buffy's good books.
Leather pants in the Buffyverse are colour coded. We have the:
Black Leather Pants of Evil (Worn by Angelus, Faith, Vampire Willow and Xander.)
Red Leather Pants of Righteousness (Worn by Buffy.)
Green Leather Pants of Jealousy (Worn by Willow.)
Pink Leather Pants of Enthrallment (Worn by Buffy.)
Angel. When Wesley makes his return as a "rogue demon hunter", he's wearing all leather. He has to change out of them though, as they chafe his...legs.
And Illyria. Oh dear Christ, Illyria.
Angelus's trademark is his leather pants, which Spike makes a hobby out of making fun of.
Parodied in one or more Benny Hill sketches. Benny plays an actor playing a bad boy dressed all in leather while filming a scene. Not only is it not sexy (cause, y'know, it's Benny Hill), the leather squeaks so much whenever he moves that it drowns out recording the dialogue, especially when he sits on a leather covered chair.
Ross on Friends tries to look cool for a date by putting on tight leather pants. Then he goes to the bathroom and finds that he can't put them back on.
Was described as a "long, hot slog in leather" and Claudia Black has been known to say that all she needed to perk her up when she was tired or burnt out was Ben to walk in wearing his leathers.
There is a reason Warren Ellis described Farscape as "one American's descent into Australia's S&M scene" (aside from him being, y'know, Warren Ellis).
Stargate Atlantis did this increasingly so as the series went on. By season five virtually the entire main cast are wearing as their standard off-world outfits: black leather jackets (McKay, Keller, and occasionally Sheppard), black leather jacket and pants (Teyla), or black leather trenchcoats (Ronon). Then there's the Wraith...
KELLY: Nothing says "Bridesmaids are easy" like short black leather.
The Ninth Doctor's signature black leather jacket on Doctor Who.
Parodied in "Smith and Jones" in which a "Slab" slave is supposedly leather all the way through. to which, the Doctor says "Someone's got one hell of a fetish"
Drop the Dead Donkey. On seeing Helen's girlfriend — a lesbian motorcycle courier — Dave provides the above page quote, while Henry is ecstatic when she straddles her motorbike.
Both heroes and villains in Blake's 7. Apparently an S&M shop made the outfits, as they had the most experience in working with leather (there's a cute anecdote about the shopworkers frantically hiding the porn and the nipple clamps when Michael Keating (Vila) turned up for a fitting with his little daughter in tow).
Especially Avon.
The Mord-Sith in Legend of the Seeker (and the Sword of Truth novels) are a blatant dominatrix archetype. With Cara a main character in season two, every episode is chock full of skin-tight red leather goodness (and somehow even more cleavage than Kahlan).
Future Claire in season 3 of Heroes has quite the black leather ensemble.
Seldom has black leather and studs looked better than on Evillll Prince Dirk Blackpool. But it just doesn't work on his brother Prince Geoffrey.
When Ryu Terui first showed up in Kamen Rider Double, he always wore a leather pants/jacket outfit in either red or black. After defeating Weather, he switched to some kind of lighter material with leather patches on the shoulders and joints in red or blue.
This seems to be the standard attire along with the Badass Longcoat for Makai Knights in GARO.
In one episode of That '70's Show Kelso gets a leather jacket because he wants to look like Brando in The Wild One. Instead everybody laughs at him for looking like Fonzie. When he throws it away in anger Hyde puts it on and immediately becomes irresistible
The Vampire Diaries gives us Damon Salvatore, who is the king of this Trope. Stefan tries, but somehow it doesn't have quite the same effect.
Alex Krycek of The X-Files is rarely seen without a black leather jacket. It's rarely the same one from episode to episode, though, since they tend to get ruined when someone (usually Mulder) beats him up.
Mulder himself has been seen wearing a leather jacket.
Leather armor is, fittingly enough, the armor of choice of rogue classes, especially in Dungeons And Dragons. Sadly, real leather armor is boiled into rigid pieces, and doesn't look or behave anything like leather clothing.
The "Leather armor" card in Munchkin.
In Vampire: The Eternal Struggle, the Leather Jacket is an equipment card. It prevents all damage from a single attack, and is then destroyed. By comparison, the Flak Jacket can be used every round, but only prevents 1 damage.
Videogames
Tequila Yuen sports a brown one and pulls it off. Maybe it's because he is Chow Yun Fat...
All of Organization XIII in the Kingdom Hearts series wear long, black leather trenchcoats. Perhaps this has something to do with their Draco in Leather Pants status among the fandom.
Haken Browning from Super Robot Taisen OG: Endless Frontier. His outfit is a black leather trench coat. He is ridiculed for complaining of overheating during the groups journey through East Elftale.
Fallout, after Mad Max above. Complete with one arm missing.
Angel Devoid, with a really Badass sounding walkloop to boot.
Psycho Mantis. The man is a villain, true, but given that his personal outfit is a few yards of leather away from being a gimp suit does help in solidifying his place as one of the most badass bosses in all the games.
He would also set you on fire with his mind for thinking of him in a sexual context.
Original poster. Sexual nothing. I'm just fascinated by the garters.
A lot of the characters in Brütal Legend, but the Fire Barons, Zaulia, and Tainted Coil are standouts.
This trope especially applies to Lita Halford, who wears a sexy outfit that consists of a midriff-baring, cleavage-enhancing leather halter top and skin-tight leather pants.
Special mention to the Baron leader who is modeled after Rob Halford, the man considered as having brought the leather fashion into Heavy Metal culture.
Ezio Auditore of Assassins Creed II back in his younger years wore leather pants that left only a bit to the imagination. It is actually Lampshaded by one of the bystander dialogues.
K' and Kula Diamond from The King of Fighters.
Flustered Lady: Such tight leather pants.
Albert Wesker of the Resident Evilused to wear just normal-looking combat gear in the first game and Code Veronica. However, he shows up in 5 wearing head-to-toe black leather complete with a leather Badass Longcoat, just in case the viewer still wasn't completely sure about his alignment.
Squall Leonhart from Final Fantasy VIII has his famous black leather and lion fur jacket and matching pants. On the opposite side, The Rival Seifer wears a white leather trenchcoat.
Sephiroth of Final Fantasy VII fame, in black. His Gackt-Expy rival Genesis from Crisis Core shops at the same place, but goes for red.
Soul Calibur's Voldo seems to have attended the Psycho mantis School of Fashion. "Siegmare" wears leather pants as well, but he's far easier on the eyes, even with a freak arm.
According to Marik, the Pharaoh's power comes from his leather pants. He was half right - apparently the Pharaoh gets his power from his leather shoes.
Benedict from Warlock Games is an interesting aversion: although he wears leather, he leaves the one fight he helps in abruptly and eventually dies offscreen.
Jim Morrison. This was memorably deconstructed by Mitch Benn in the intro to his song "Stinky Pants":
"Given that Morrison seems to be wearing the same pair of leather trousers in every picture there is of him, and given how difficult it is to clean leather properly, assuming you even try, I don't imagine you'd have wanted to stand downwind of the Lizard King."
Gerard Way from My Chemical Romance used to wear leather jackets until they fell apart. See above, speculation on how bad Jim Morrison's pants smelled.
"I have a leather jacket that could turn your stomach..."
Joan Jett is a good female example of this- she's frequently seen in leather pants or jackets, or head-to-toe leather outfits. (Though if the leather flag sticker on her guitar is indication, this may be more than just a fashion choice.)
Many metal artists, including Trope NamerRob Halford with a similarly titled Judas Priest song. Ironically, Halford himself prefers pleather so as not to sacrifice innocent cattle, and the song title itself was originally used in the theme to Rawhide, though these days it's more associated with Halford and Judas Priest than anything else.
Red Commissars and Chekists of the Russian Civil War era. Their uniform included a black leather peaked cap (replaced with a red headscarf for female commissars), a black leather jacket and jackboots. Particularly Ksanka in the Soviet action movie The Crown Of The Russian Empire, or The Elusives Again.
The crew of Trotsky's personal armored locomotive train wore red leather outfits — military-style jackets, pants, jackboots, and hats that looked sort of like ushankas.
Younger panzer crews in Nazi Germany, particularly in regiments which were formed in the middle to late war years, were fond of wearing U-boat crew leathers.
Both of the above had practical considerations, as both train crews and panzer crews were working with hot machinery that could probably set cloth on fire. Plus it really did look pretty badass. So... yeah.
Many steam-locomotive crews wore either a jacket or a vest made of thick black leather, to aid in protection from inclement weather in the open cabin and from searing-hot metal parts. Knowing how dirty one gets when dealing with coal dust and also how dirty is the job of lubricating the running gear of the locomotive with grease guns and oil dripper cans, they were worse than Jim Morrison.
Los Angeles-based clothing designers Lip Service are quite fond of this, as it's been their longest running line for about 15 years.
