Light Feminine and Dark Feminine

This is a character contrast trope. Both female characters are decidedly feminine, but in different ways. The Light feminine is generally angelic and feels love. The Dark feminine is generally devilish and plays with desire. Either type can be the girly girl portrayed in the Tomboy and Girly Girl contrast. When a love interest is involved, it's likely to lead to a Betty and Veronica love triangle: Betty being the Light feminine, and Veronica being the Dark feminine.

As with any two character trope, the two characters have to have some sort of relationship with each other, be it friends, family, love interests, or rivals for a love interest, so the two characters can be playing the traits directly off each other.

The dark feminine character is not a villain or a whore but half of a good girl, bad girl or naughty and nice pair. Remember not to put a square peg in a round trope. Remember Dark Is Not Evil.

Compare The Three Faces of Eve. The Spear Counterpart is Noble Male, Roguish Male.

Examples of Light Feminine and Dark Feminine include:

Anime and Manga

The manipulative and deceptive Haruhi, and the meek and mild Mikuru, from Haruhi Suzumiya.
The Silk Hiding Steel Haruna and the Genki Girl Yui in Corrector Yui.
Nanako Misonou and Mariko Shinobu from Oniisama e..., contrasting with the Bifauxnen and Ladette duo of Rei and Kaoru. While cute, mild-mannerd Nanako sits firmly on the Yamato Nadeshiko spectrum, Mariko is a fair-skinned, raven-haired Yandere (with shades of Tsundere) from day one.
In Yu-Gi-Oh!, Mai Valentine/Kujaku plays Dark Feminine to first Tea/Anzu's and then Serenity/Shizuka's Light Feminine.
There's more of one of these duos in Bleach. I.e., Rangiku Matsumoto is a good Dark Feminine due to her Bottle Fairy and Ms. Fanservice sides, and she has two prospect Light Feminines: Barrier Warrior Orihime Inoue and Nicegirl Momo Hinamori, with whom she occasionally doubles as Lovely Angels.
Mawaru Penguindrum gives us Himari Takakura (Silk Hiding Steel Girl Next Door) and either Masako Natsume (Action Girl Large Ham) or Yuri Tokikago (Badass Normal who swears by the Rule of Glamorous).
Detective Conan: Yukiko Kudo and Sharon Vineyard aka Vermouth.
Puella Magi Madoka Magica:
- Homura Akemi embodies both sides. She starts as "Light" as she's a shy, clumsy and kind Meganekko, then switches to Dark as she reinvents herself as a Tall, Dark and Bishoujo Dark Magical Girl.
- For Madoka, it's Mami (Light) vs. Homura (Dark) (but see also the spoilered part above). For Mami, it's Madoka (Light) vs. Kyouko (Dark). For Yuma, it's Mami (Light) vs. Kyouko (Dark).
Fullmetal Alchemist has the Elric brothers, Roy Mustang, and Mustang's five subordinates versus the Big Bad and the seven Homunculi, who represent the seven deadly sins. There's one female in each group of eight - Riza Hawkeye as Light Feminine, Lust as Dark Feminine.
Princess Tutu has Ahiru/Duck as Light Feminine and Rue as Dark Feminine. The former is a cheerful and clumsy Genki Girl whose mission in life is simply to her love interest Mytho to smile. The latter is an elegant and aloof Ojou who also loves Mytho, but in a far more possesive way. Both girls have white and black costumes of their respective Magical Girl personas, Princess Tutu and Princess Kraehe. Also, they're both based on Odette and Odile from the ballet Swan Lake.
Bitter Virgin has manipulative, vain Kazuki as Dark Feminine and meek, childlike Hinako as Light Feminine.
- Yuzu might feet as well as Light, what with being the local Unlucky Childhood Friend.
Umineko no Naku Koro ni has kind, motherly Shannon and decadent, sadistic Beatrice. Of course, since the two are one and the same, Beatrice becomes more Light Feminine as the series goes on.
Gundam Seed Destiny invokes the trope with the softspoken, Yamato Nadeshiko-like Idol Singer Lacus Clyne and her much Hotter and Sexier Body Double, Meer Campbell.

Comic Book

In Bone, Rose is the Light Feminine, while her twin sister Briar is the Dark Feminine.

Film

Gentlemen Prefer Blondes: Russell is the Dark Feminine, while Monroe is the Light Feminine.
Sunrise: The Woman from The City is the Dark Feminine (hedonist, cheater), while The Wife is the Light Feminine (goody-goody all the way through).
Batman Forever has Two-Face's molls, Sugar (played by Drew Barrymore) and Spice (played by Debi Mazar). Subverted in that both of them are "bad", and "Sugar" is probably worse because she gives The Riddler the cube with the information about Bruce Wayne's Secret Identity.
Discussed in Black Swan.
Pepper Potts and Natasha Romanoff/"Natalie Rushman" in Iron Man 2 and The Avengers.

Literature

Gone with the Wind: Melanie is the Light Feminine, while Scarlett is the Dark Feminine.
The Jack Weyland book Michelle and Debra has the obedient Michelle as the light and her rebellious best friend Debra as the dark.
The two leading ladies in Nathaniel Hawthorne's The Blithedale Romance. Priscilla is the demure, fragile, domestic (read: conservative) Light Feminine; Zenobia is the mysterious, sensual, outspoken, transcendental feminist (read: liberal) Dark Feminine.
In Animorphs, Cassie and Rachel have shades of this: Cassie is a down-to-earth Friend to All Living Things who only fights the Yeerks because she has to, while Rachel is a borderline-Dark Action Girl who honestly enjoys the war on some level, despite having the appearance and fashion-obsession of a supermodel. Despite all this, they're also best friends.
Ellony Leckery and Pharinet Palindrake in Chronicles of Magravandias, Ellony being a straight example of The Ingenue while Pharinet is something of a Yandere when pushed. Other female characters in the story, particularly those who fill similar roles or are related to them or are named for them are more balanced between the two extremes.
Antonia and Matilda in The Monk, as highlighted by Ambrosio's interest in both of them, their similar appearance, and the roles each of them play in the story.

Live Action Television

Two Broke Girls: Max is the Dark Feminine, Caroline is the Light Feminine.
- Lampshaded by Sophie, the title character in "And the Upstairs Neighbor", when she compares them to a chocolate and vanilla cupcake respectively.
June (light) and Chloe (dark) in Don't Trust the B---- In Apartment 23
Degrassi has the noble Emma as light and her best friend the provocative Manny as dark.
In Buffy the Vampire Slayer there are the two slayers, the responsible Buffy and the destructive Faith.
How I Met Your Mother has the motherly, married, Girl Next Door Lily and the vain, independent, sexy Robin.
Merlin has Guinevere, the good hearted heroine, and Morgana, the villainess.
- Though interestingly, Gwen is linked more with desire than Morgana, who (despite a couple of early Femme Fatale scenes) almost comes across as asexual in her complete lack of interest in men.
Robin Hood had Marian as the light feminine, who was replaced by Isabella, the dark feminine.
The Fresh Prince of Bel-Air: Hilary (dark) and Ashley (light).
Xena: Warrior Princess (dark) and Gabrielle (light). Granted, Xena was a Tomboy Princess, but in her first appearance she was also quite decidedly The Vamp.
Most of the final two contestants of America's Next Top Model counts: Cycle 1's Adrienne (dark) and Shannon (light), Cycle 2's Yohanna (dark) and Mercedes (light), Cycle 3's Eva (dark) and Yaya (light), Cycle 4's Naima (dark) and Kahlen (light), Cycle 5's Nicole (light) and Nik (dark), Cycle 7's CariDee (light) and Melrose (dark), Cycle 10's Whitney (dark) and Anya (light), Cycle 14's Krista (dark) and Raina (light), Cycle 15's Ann (light) and Chelsea (dark), Cycle 16's Brittani (light) and Molly (dark), and Cycle 17's Lisa (dark) and Allison (light).
New Girl: Jess is the Light Feminine while Cece is the Dark Feminine.
Snow White and Red Riding Hood from Once Upon a Time. It's practically in their names!

Mythology

In an apocryphal Abrahamic mythology, Lilith (the first wife of Adam) represents the Dark Feminine—while Eve (Adam's second wife) is the Light Feminine.

Newspaper Comics

Non Sequitur: Kate is the Light Feminine, while Danae is the Dark Feminine.

Video Games

Shin Megami Tensei I has Yuki (Light) and Yuriko (Dark) Yuriko is actually Lilith, making this a religious shoutout.
Catherine: Catherine is the Dark Feminine, while Katherine is the Light Feminine.
Dragon Age Origins: Leliana is the Light Feminine, while Morrigan is the Dark Feminine. Leliana is eventually revealed as a subversion of the trope, while Morrigan will defrosts as the game progresses. Hence standard BioWare deconstruction takes place. The same pattern is followed in the sequel Dragon Age 2 with Merrill (light) and Isabela (dark)
The two female love interests in Mass Effect 1 are Liara (young, naive, virginal academic) and Ashley (gun-toting, suspicious of aliens, snarky soldier) largely follow the trope.
Final Fantasy X: Lulu is the Dark Feminine, while Yuna is the Light Feminine.
Overlord: The potential queens fall into this. In the second game, the first two mistresses fall into Tomboy and Girly Girl—but also serve as a collective "Light Feminine" to the third.
Fire Emblem 7: The Shrinking Violet Florina has these dynamics with Serra (a borderline Fashionista as well as a White Magician Girl), Fiora (a more self-assured Lady of War) and Nino (an Black Magician Girl). She falls more into Tomboy and Girly Girl with Farina and Lyn, and with Ninian it's unclear because they are both very Light Feminine.
Fire Emblem: The Sacred Stones gives us Eirika and L'Arachel. Eirika is a gentle Lady of War and The Messiah, L'Arachel is a bombastic Genki Girl.
The light goddess Palutena and and dark goddess Medusa of Kid Icarus are literal examples of this trope.
The Yamato Nadeshiko Lilly Satou from Katawa Shoujo is the girly girl to her Bifauxnen sister Akira, AND the Light Feminine to Shizune Hakamichi's Ms. Fanservice Dark Feminine.
Ar tonelico II: Melody of Metafalica: Cloche (Light) vs. Jakuri (Pitch Black). Luca is kinda shady.
Aoi Shiro: Nami (Light) vs. Kohaku (Dark - she's not even very feminine), former lovers (or something to that effect).
Akai Ito: Yumei (Light) vs. Nozomi (Dark), archenemies. Both of them are very feminine.
Touhou: Reimu vs. Marisa, rivals. Satori vs. Koishi, sisters. Keine vs. Mokou, very close friends. The Aki sisters.
The Florian Sisters of Magical Girl Lyrical Nanoha A's Portable: The Gears of Destiny. The caring Idiot Hero of a big sister Amita serves as the Light Feminine, while the coy, flirty, and cynical little sister Kyrie serves as the Dark Feminine.
Chun Li and Juri Han from Street Fighter IV. Both women are Kick Chicks, but while Chun Li is an Action Girl who's very firmly on the side of good, Juri is a mix of Bastard Girlfriend and Dark Action Girl.

Western Animation

Adventure Time: Marceline is the Dark Feminine, while Bubblegum is the Light Feminine.
My Little Pony Friendship Is Magic:
- Fluttershy (Light) is kind, caring, very much like a mother to the animals. Rarity (Dark) is vain and slightly manipulative, but still a good-hearted pony.
- This contrast is also readily apparent in the princesses. Celestia tends to act motherly and patient towards her subjects, while Luna is more intimidating and impulsive.
- Another possible pair of characters to display this contrast is Pinkie Pie and Twilight Sparkle. Pinkie is Light, in that she tries to make everypony happy and operates primarily on intuition. Twilight is Dark, having a prideful and slightly selfish streak and operates primarily on logic, although, like Rarity, she's still a good-hearted pony.
G.I. Joe Scarlett is light feminine while Jinks is dark feminine.
With regard to Northern Water Tribe social norms, in the first season of Avatar: The Last Airbender, the dutiful, self-sacrificing Yue is Light Feminine and rebellious Action Girl Katara is Dark Feminine. However, Katara is arguably the Light Feminine when compared to the series' other Action Girls due to her unofficial status as everyone's mom.
Total Drama: Heather is Dark Feminine while Lindsay is Light Feminine.