Devoted to You

"Why is everyone so hot for this girl? Has she got beer-flavored nipples?"

—Patrick Verona, 10 Things I Hate About You

Some ladies (or men) are just special. With no conscious action on their part, they are able to create an almost inescapable devotion in would-be suitors. Neither time nor distance can tame this obsession, and in the unlikely event that it does fade, the slightest contact with the woman will bring the obsession back, often stronger than it was before. Often there is no real explanation given for this level of obsessed devotion in comparison to other women (or men) in the series.

Usually a woman, and can come from almost any background: An Ordinary High School Student, a Girl Next Door, an Action Girl, Idol Singer, Tsundere, Beautiful All Along, or a recent widow, Tall, Dark and Handsome, Jerk with a Heart of Gold, Unlucky Everydude.

Related to the Chick Magnet, with a few key differences:

Rarely has more than 1 or 2 men chasing her at a time.
There is rarely an Unwanted Harem
In Shonen and Seinen stories, is usually not the main character, in Shojo or Josei stories, almost always is.

What defines this Love Interest is the single minded devotion that is given to him. Even though she might not be the most attractive, wealthy, or interesting female in the group, her devotees will often discard any and all advances made by other women, up to and including no strings attached sex. Alternate takes are lovers who had to leave the girl for "her own good" often among tons of Wangst. But he will always be in their hearts, and none of their attempts to move on can possibly succeed. Prone to have a Hopeless Suitor, Dogged Nice Guy, or maybe even a Stalker with a Crush.

May not always be the True Love of the main character, but since the main has become a Hopeless Suitor he can't notice. This often results in a Type 5 Love Triangle. Sometimes, one of the two men going after her will gracefully bow out, promptly find a new girlfriend, and step aside for the new guy who will be obsessed to show up within an episode or two. (see Marmalade Boy).

Other common Triangle Types stemming from this trope are types 3, 4, 7, and 10.

Usually virginal, she is never a slut. Compare Hello, Nurse! and Even the Girls Want Her which usually don't apply, but is sometimes part of the package.

Romance writer Lani Diane Rich refers to this sort of thing as having a Glittery Hoo-Ha.

Examples of Devoted to You include:

Anime and Manga

Kyoko Otonashi from Maison Ikkoku is a classic example, as both Unlucky Everydude Godai, and Bishie Sparkling Mitaka, are in a constant state of turning down many of their romantic prospects on the off chance that Kyoko is interested in them.
Ayukawa Madoka from Kimagure Orange Road: Kasuga Kyosuke is dating a cute girl named Hikaru, but it's her best friend Madoka who has his devotion.
Suzuka from Suzuka: The eponymous character of this show, as Yamato even when in other relationships, is obsessed with her. In the manga, he turns down other women who are interested in him, and even flat out refuses sex because of his obsession.
Lynn Minmei from Macross: Hikaru Ichijo is obsessed with her throughout much of the series, even when she specifically states she is interested in someone else. He begins to get over it, but falls right back in after seeing her face.
- Ultimately subverted when Hikaru moves on and ends up marrying the other vertex of the Love Triangle, Misa Hayase.
Myung Fang Long from Macross Plus is obsessed over by Guld and Isamu after a several year absence. Isamu even leaves behind his new girlfriend, because of her.
Belldandy of Ah! My Goddess, justified in that she is literally a Goddess.
- Everyone is devoted to Belldandy. You'd be crazy not to be.
In Yume De Aetara, the Official Couple of Masuo and Nagisa manage to catch each one some suitors of this kind. In fact, Masuo was one of these for Nagisa, but ascends to real Love Interest because his devotion and interest are proven as more genuine than his rival's.
Pandora Hearts: So much.
- Gil towards Oz.
- Oz and Jack towards Alice.
- Glen and Jack (The latter probably moreso) to Lacie, which essentially fuels the plot.
- Lottie towards Glen.
- The entire Baskerville faction to Glen.
  - and also Jack towards Glen. "...My one and only best friend."
- Break towards Sharon and her family.
Gokudera towards Tsuna in Katekyo Hitman Reborn.

Film

The entire plot of There's Something About Mary was based on the eponymous character being one of these.
Allison from Get Over It: Is a perfect example that the main character has to get over in order to meet his true love.
From Grease, Hopelessly Devoted To You!
Mikaela from the Transformers film series.
Kevin James' Love Interest in Hitch.

Literature

Bella Swan from Twilight, which is just one of the reasons she is considered a Mary Sue.
Ginny Weasley from Harry Potter. Though she's had other boyfriends before him, she's always been in love with Harry. Even after they break up for a time, she remains fiercely loyal to him.
Both lampshaded and justified with Lotus Cloud in Bridge of Birds—this is part of the evidence that she's actually a goddess.

Live Action TV

Buffy from Buffy the Vampire Slayer: Both Angel and Spike are classic examples of characters held in thrall by Buffy. Both before and after being with Buffy, they were creepy stalkers.
Veronica Mars: Duncan and Logan pretty much unable to ever forget Veronica, no matter how hard they try.
Winifred Burkle from Angel: both Gunn and Wesley obsessed about her before and after their relationships.
Lana Lang of Smallville.
Rory of Gilmore Girls.
Noah's Arc: Noah seems to have continuous access to deeply dedicated boyfriends, with little real effort on his part. At one point even a millionaire rapper pursues him.
Sookie Stackhouse from True Blood comes to mind. She's attractive, and can read minds, but Vampire Bill and Sam pretty much can't go for 30 seconds without thinking about her.
Olive from Pushing Daisies even sings I'm Hopelessly Devoted To You! once.
Delenn of Babylon 5. John Sheridan, of course, is hopelessly, passionately in love with her, and she returns his affection in equal measure. But her attache Lennier is also head-over-heels in love with her, and he has no chance whatsoever because Delenn is just as starry-eyed over Sheridan as Sheridan is over her.

Music

Video Games

In Final Fantasy IV Kain is willing to betray his best friend of years in order to gain the love of Rosa, Cecil's lover.