Asuka Saginomiya (鷺ノ宮 飛鳥 Saginomiya Asuka?), also known as Asuka, the White Lily, is a manga-only character who's an old acquaintance and rival of Kodachi Kuno, who she has known since childhood. The two tried "out do" each other by trying to get the best looking boyfriend. However, an argument ensued and the disagreement was never settled.
Asuka means "Tomorrow Beautiful," the beauty part is in reference to her stunning good looks. Saginomiya means "Fraud Princess" in regards to her actual personality.
Due to her being purposefully being the rival of Kodachi, Asuka has a very similar personality. Examples of include how when Asuka sets traps in the Tendo Dojo (described by Kodachi as cowardly), Akane initially believes that was Kodachi who set them as she is the most likely to do such a thing. Asuka's willingness to do anything to win is also a reflection of how Kodachi tried multiple different cheating techniques in her Martial Arts Rhythmic Gymnastics match against Ranma Saotome, including having the whole St. Hebereke gymnastics team underneath the ring so she could always land back in it.
She always carries an empty frame and a bouquet of white lilies to quickly pose as a living portrait of herself.
Ten years prior to the events of the series, Asuka and Kodachi were both attending the Lizard Kindergarten and at play time the teacher asked the boys to hold hands with the girls and after Kodachi was "chosen" by A-kun (the coolest boy in the class), Asuka threw an explosive Lily at him and told Kodachi that her B-kun was much cooler.
The two then begin throwing several explosive Roses and Lilies at the other's letter-kun and ultimately Kodachi won, but A-kun never recovered. Losing upset Asuka who told Kodachi that in ten years they'll have a rematch to compare boyfriends, which Kodachi accepts.
The time of the rematch came and Asuka sent a letter to Kodachi, summoning her to the local Carnival. When Kodachi arrives she initially forgets about the challenge, but remembers when Asuka throws an explosive Lily at her, which Kodachi catches and throws back. Asuka, who's on the back of a horse, tells Kodachi she seems in good health and is still playing around as usual. Asuka then dismounts her horse (which turns out to be nothing more than a Carousel horse) and asks Kodachi if she remembers, Kodachi then remembers the challenge that was set ten years ago and uses a smoke screen to escape, leaving Asuka behind shouting to her to get back here.
The night, after Kodachi explains to Ranma and Akane (who was at the Carnival when Asuka appeared) about the challenge from ten years ago, Asuka arrives at the Tendo Dojo training hall and sets up some traps which Ranma quickly sets off. A portrait of Asuka then appears in the corner of the training hall, but it begins to laugh and turns out to be the actual Asuka holding the picture frame.
Asuka says she came to check things out herself, she then sees Ranma unconscious on the floor and decides to leave, but Akane tells her to wait a minute and chases after her. Akane tries to get Asuka to stop this fight between her and Kodachi since Ranma is her (Akane's) fiancé. However, before Akane can tell this to Asuka completely she interrupts saying that during the last ten years she's been seeking the perfect man but if Kodachi's settled with a fool like Ranma she's already won.
The next day Asuka is in some Zoological gardens and thinks to herself about how Kodachi and her fool boyfriend will fall at the sight of her ultimate boyfriend. She then laughes very loudly, to the annoyance of some other visitors to the garden who say that's against the rules (a large sign says not to laugh loudly in the gardens). While Kodachi tries to get Ranma to herself, Asuka throws an exploding Lily which is quickly followed by a herd of cattle that end up stampeding over Ranma.
While Kodachi looks at Ranma in horror of what happened to him, Asuka rides in on a cattle and sees the knocked out Ranma and tells Kodachi that he's just right for her. This angers Kodachi who asks Asuka how her Ranma looks like a child's balloon with scribbles on it, to which Asuka retorts that she was about to say that. Kodachi then decides she'll find and kill Asuka's boyfriend so Asuka gives chase of Kodachi, not before she runs over Ranma again.
Kodachi arrives at the gardens and throws an explosive Rose at who she believes to be Asuka's boyfriend, but it turns out not to be. Asuka catches up and tells Kodachi she's quite careless and points out where her boyfriend is. Kodachi then throws an explosive Rose, however, it turns out Asuka's boyfriend is wearing a suit or armour that Asuka told him to wear as she thought something like this may happen.
Just before Kodachi attacks Asuka's boyfriend, Ranma appears and tells her this is meant to be a fair fight (Asuka is surprised by how much better Kodachi's boyfriend looks compared to earlier). Akane then smugly asks Asuka if she's going to show them her boyfriend, this angers Asuka and Kodachi who tell Akane this is between them. Meanwhile, Asuka's boyfriend complains of the heat inside the suit and takes his helmet off, revealing his beauty. Seeing his face both Kodachi and Akane admit defeat.
As Asuka celebrates her victory over Kodachi, the actual girlfriend of the man in the suit of armour appears and the two walk away, returning to their date. Kodachi then laughs at Asuka that it appears that this is a draw, Asuka agrees and tells Kodachi that they'll duel again in five years.
Asuka isn't shown to have many abilities. However, of the abilities Asuka does use they seem to be near carbon copies of those by Kodachi which don't involve using Rhythmic Gymnastics equipment. The most frequent example of this is how Asuka uses explosive lilies as her primary weapon which mimics the explosive roses used by Kodachi. Asuka is also known for using chloroform to knock out her targets, such as her "boyfriend".
With Kodachi: Asuka has a very negative relationship with Kodachi, all stemming from the challenge that was set while they were both in kindergarten.
With Akane: Due to her concentrating on Kodachi more than Akane, Asuka generally seems to ignore Akane. However, Akane is very angry with Asuka after she declared that if Ranma is Kodachi's boyfriend then she had already won. This makes the angered Akane decide to help Kodachi improve Ranma's appearance so she can win the competition between Kodachi and Asuka.