Dark hair and pale skin as an indication that a character is beautiful. In western culture, this is a once-dead, now reviving trope, thanks to the Goth and Retro movements bringing an increased awareness of this and the 1950s pin-up style regaining popularity. In addition, the current vampire fad and the rising fear of skin cancer have helped with the resurgence of this trope. This is also quite popular in Eastern media, being the traditional standard of Asian beauty, and the fact that most of the Japanese population has black or very dark brown hair helps. The high contrast also makes for a striking and visually appealing appearance.
Commonly a requirement for the Yamato Nadeshiko type and is also known as the Yamato Nadeshiko look. In fact, a Raven Hair, Ivory SkinYamato Nadeshiko is a stock character for the Harem Genre.
There is crossover between this look and Eerie Pale-Skinned Brunette, in the form of attractive Goths, beautiful vampires, and other characters who manage to be both creepy and beautiful.
Contrast Eerie Pale-Skinned Brunette, where this look is seen as, well, eerie, and But Not Too White. Compare Dark-Skinned Blond, its visual inverse.
And please, people, before adding to this list, consider whether or not the character was clearly meant to be attractive, explicitly stated to be attractive, and/or regarded as attractive by any other characters. Do not add them to this list just because you find them to be attractive. Because of that, No Real Life Examples, Please!.
Black Jack: one episode featured a strong example of this — Souno, a Yamato Nadeshiko young girl from an old and rather traditional Japanese family, who had been kept indoors all her life due to suffering form a debilitating disease that would cause her life to drastically shorten if she was exposed to sunlight (as well as killing her off before she turns 18 even if she avoids it). She's spent most of her life in a sealed room, practicing Ikebana, the Japanese art of flower arrangement, under the watch of her very severe Overprotective Dad; thus, Souno is perfectly pale, with perfectly black hair, and a perfectly exquisite face...a beauty in a bottle. (Remember, the "Nadesico" part of Yamato Nadeshiko refers to a particular type of flower — probably a deliberate parallel in this case.) Fortunately, Doctor Blackjack is there to help — along with his lively assistant, Pinoco, who strikes a really cute Inter Generational Friendship (sorta) with Souno and gives her the courage to get the treatment she needs.
Negi is awestruck when he accidentally spies on Setsuna in the bath, because of her incredibly pale skin and raven-black hair. Chamo even refers to her as a Yamato Nadeshiko due to her looks! She later turns out to be a Heroic Albino; her hair is dyed to fit in better.
Konoka is also seen as this when she wears a kimono to school.
Mariko Shinobu and "Mona Lisa" Komabayashi (who's nicknamed "Mona Lisa" both for her stoic attitude and her Tall, Dark and Bishoujo looks) from Oniisama E.
Kaede Rukawa of Slam Dunk is incredibly pale and handsome. Ironically, he tans the easiest out of everyone.
This trope is quite popular in 1950s pin-ups, and modern women like Rita Von Squeeze have helped bring the art style back to life.
Comic Books
Death and Desire from The Sandman qualify (two other members of the Endless have the right hair and skin for it, but Morpheus is extremely gaunt and Looks Like Cesare and Despair is a Gonk); Death was based on a myth (Kabbalistic, I think) in which the Angel of Death appears to the deceased as a woman so beautiful their soul leaves their body in ecstasy, and, being the personification of desire and all, Desire is (supposed to be) the embodiment of perfect androgynous beauty.
It isn't so much as mentioned in A Knight's Tale, but Kate the Blacksmith is downright stunning with her classic Caledonian coloring of milky pale skin, dense black hair, and blue eyes.
The titular character of La Reine Margot, as played by Isabelle Adjani who actually has this coloring.
The heroine of Snow White retelling Snow White A Tale Of Terror of course has this coloring. Monica Keena, a natural blonde, dyed her hair black for the film.
... there she stood, raven-haired and violet-eyed, snowy fair and finely fit, as if carved by the gods from a solid block of desire.
The Gemma Doyle Trilogy's Pippa is renowned for her beauty and fits this trope to a T.
J. R. R. Tolkien's use mixes Author Appeal and, presumably, Celtic notions of beauty, since the Celts (flanderized as Fiery Redheads) were actually mostly dark-haired and apparently regarded this as the ideal, so most of Tolkien's most important beautiful characters are dark-haired, pale-skinned, and have Gray Eyes. Particularly notable examples include Luthien from The Silmarillion and Arwen from The Lord of the Rings.
Romance of the Three Kingdoms: the Qiao sisters were this, and the book plays up that part of the reason Chi Bi happened was that Cao Cao was after them because of this trope.
The titular characters of Edgar Allan Poe's Berenice and Ligeia.
Eve Orcaczy from the rather obscure short story Each Man Kills. She's also an Eerie Pale-Skinned Brunette, since she's a vampire, but she is described as exceptionally beautiful.
Scarlett O'Hara, the heroine of Gone with the Wind, has black hair and very fair skin.
Many tragic heroines in 18th century Gothic Horror novels are described this way.
Yennefer from The Witcher books. She is pale with raven black hair and wears only black and white. Like all sorceresses, she is incredibly beautiful.
Irene/Attolia from The Queen's Thief is one (fair skin, very beautiful, dark haired).
Inverted in Fairest with Ava, described to have black hair and pale skin, but is ugly.
Several of Robert E. Howard's Conan the Barbarian stories use this trope. Many of the women that Conan becomes involved with are described as having dark hair and pale skin, some of the more notable ones being the pirate queen Belit and the slave girl Zenobia.
A male example is Naoise, lover of Deirdre in the Ulster Cycle of Celtic Mythology.
Deirdre:(After seeing a raven drinking blood out of the snow) I will love a man with hair the color of the raven, skin as white as snow, and lips as red as blood.
Video Games
In Persona 4, Yukiko Amagi is seen as this and gathers quite a fan club because her looks.
If someone in Fire Emblem 7 is about to describe a Morph, there's likely three features to be mentioned: "1. Pale skin, 2. Hair like ebony*
but it really looks purple
, and 3. Eyes of Gold". Sonia was actually made to be beautiful and to seduce Brendan Reed.
In Sengoku Basara, we have Oichi (who was a certified Real Life example) and her sister-in-law, Nouhime.
Setsuka in Soul Calibur 3. She's actually a natural blonde, however; she dyes her hair to fit in, in Japanese society.
Miranda Lawson in Mass Effect 2 is much paler than most inhabitants of the Mass Effect universe, has jet-black hair, and is regarded as extraordinarily attractive.
Final Fantasy VII: Vincent is a male example, with long black hair and white skin. Also somewhat subverted as Yuffie has black hair and pale skin, but is not particularly thought of as beautiful.
Two of the five princesses depicted in the second Dark Parables game have this; of course, one of them isSnow White.
Ashei, the lady knight in The Legend Of Zelda Twilight Princess, has the physical characteristics of this trope, but whether other characters consider her beautiful is never stated.