Ryōko Asuka

is a blonde member of Red Tail. She always wears a medical mask and rarely talks.

Appearance
Ryoko has long, blonde hair, styled in a similar fashion to Shizuka Nanami's, though it is messier and her bangs often fall over her right eye and is always seen wearing a medical mask. She is sometimes seen wearing her school's uniform.

Personality
She has a delinquent-like personality and doesn't hesitate to make daring comments about others. She is usually seen with Yuka Hanazawa. Despite this, she actually never skipping school as evident in Episode 45.

Tōhōshinki Arc
Her first appearance was during Tatsumi Oga's, Hajime Kanzaki's and Tatsuya Himekawa's assault on Ishiyama to confront Tojo. However, they were blocked by delinquents who were apparently promised to that if they took down the trio they would united under Tojo. Aoi Kunieda intervenes with Red Tail at her side.

Saint Ishiyama Academy Arc
She and Hanazawa are seen eating together in their flashback concerning Takeshi Shiroyama's injury. They blame themselves for what happens and this throws Kanzaki into an uncontrollable rage. She appears as a support character taking the outfit of a cheerleader during the volleyball match between the Six Holy Knights and the Ishiyama Gang.

Prince En Arc
Seen as a supporting character when Yuka Hanazawa asks her to cover for the missing Ishiyama students.

Mobichi Arc
When Furuichi asks that Aoi take him to the school infirmary, Ryōko inquires whether a lolicon such as himself actually just asked that. Ryōko later remains in her homeroom.

Ryōko later accompanies her fellow Red Tail to the local river, where they are joined up with several of their peers.

Saint Saint X'mas Arc
During lunch, Ryōko sits with the rest of the Red Tail and listens to Yuka as she explains of the Saint Saint X'mas competition.

Return to Ishiyama High School Arc
One day, she and the other Red Tail members find Aoi writing fortune cookie messages. Ryōko tells Aoi that they will help her write them.

Ryōko eventually heads back to Ishiyama during the new semester following its second reconstruction. As she hangs out on the rooftop with the other Red Tail girls, she discovers that Yuka evidently has little knowledge about the "Killer Six Elements", irritating Ryōko. Ryōko later points out to Nene that Yuka still doesn't understand after listening to her explanation.

Later in the afternoon, several of the Red Tail, including Ryōko, head to the Kunieda residence where they see an injured Aoi being tended to her wounds by her grandfather. Ryōko is worried about her former leader and asks whether she is seriously hurt. Aoi explains that she is fine, though the ones who attacked her were from Majōgari Academy, apparently led by Ringo Hōjō; upon hearing the name of Aoi's predecessor, an already-anxious Ryōko grows shocked.

A meeting is eventually held outside; among the attendees are the other Red Tail and Tōhōshinki. Ryōko is initially worried about Tōjō's absence; after hearing Natsume's theory, she wonders whether the "Killer Six Elements" have already taken down the "beast". However, her suspicions lower when Jinno confirms that he is perfectly fine. The delinquents' meeting soon commences and, following a series of back-and-forth conversation, they all decide to gather information on their enemies before launching an attack; moreover, a private fight will be held between Yōhei Nasu and Tatsumi Oga. Problems soon arise with Kanzaki's and Himekawa's disapproval of Oga as their leader. When Yuka suggests a game of rock-paper-scissors to solve the issue, Ryōko hesitantly says that she is fine with the idea, subsequently leading to everyone present into participating. The results conclude with Baby Beel being the leader of their alliance.

The following day, while the other delinquents are busy gathering information on the Poltergeists, Ryōko and Umemiya hang out in one of the classrooms. Both of the girls later find out that a party with Oga and Kanzaki has recently taken out Nasu's group. Shortly after, they are approached by Yuka who tells them about how one of the Poltergeists' face melted before her very eyes; hearing this leaves Ryōko skeptical and she tries reasoning with Yuka by bringing up the "Girl Who Cried Wolf" tall tale. However, the two end up telling Yuka about the events regarding Oga and Nasu before quickly moving on to the top of Ringo Hōjō. Ryōko, who is more aware of the former leader's nature than the others, is inquired of her personality; she simply states that Ringo is a "witch".

The three are later told by Furuichi that Aoi is supposedly going to fight Ringo; both Ryōko and Umemiya are particularly unsurprised at the situation. However, they become excited when they see Nene appear and happily agree to accompany her to the front lines. As they stroll the hallways, they are confronted by the "Reborn Red Tail". Ryōko tells the girls to get out of their way. Both generations then clash with one another; unfortunately, all members of the Red Tail are badly beaten and defeated.

They are subsequently taken to a desolate area within the school with Aoi and Ringo inside. Upon their arrival, Ringo proposes that Aoi fight either Nene or Oga for the other's safety or otherwise be beaten along with all of them. Ryōko screams for Aoi to fight back. Aoi eventually does and she even succeeds in dealing a powerful technique against Ringo. Not long after, she proclaims to the people around her that she has decided to become the Red Tail's leader again, which causes Ryōko to smile.

Ringo later rises back up, seething with anger at Aoi's declaration and another remark from the now-freed Oga. While caught up in rage, she launches a striking attack at Oga with power that bewilders Ryōko, who becomes worried that Ringo is truly just as powerful as Aoi. She continues to watch the leaders' fight; when members of the "Reborn Red Tail" appear to assist Ringo, Ryōko yells to Aoi that they all have a strange power within them. Nonetheless, Aoi attains victory in the end.

Powers & Abilities
As a member of Red Tail, it can be assured Asuka is a capable fighter on her own. However unlike the other members of Red Tail she doesn't appear to wield a weapon, but in the later chapters and episodes she is seen holding some kind of badge with Japanese characters on it. On closer inspection the badge has some sort of groove in it, giving it the vague appearance of a yo-yo. On one occasion she wields a kendo stick, but not for too long to make it her trademark weapon.

Red Tail
a member of Red Tail, she always supports them.

Yuka Hanazawa
She and Hanazawa appear to be close friends and are often seen together. It is revealed that both of them are skilled at hair styling when they offer Tatsuya Himekawa to bring his trademark pompadour down. Yuka also asks her to cover for the missing Ishiyama students while they go searching for Prince En.

Kaoru Umemiya
Kaoru is one of Ryoko's close friend. They usually were seen together. There's a scene that they eat lunch together and when the others play a game at Himekawa's house, the two don’t go.

Quotes

 * "We ain't gonna let anyone drag Madame Aoi down...": when she and Hanazawa were about to take Himekawa's trademark pompadour down.
 * "Don't say it...": when Hanazawa was about to express her insecurities while bathing with the presence of Hilda

Trivia

 * Asuka has taken her mask off four times. Once when she was eating lunch with Yuka Hanazawa at Saint Ishiyama Academy, the second time in her flashback when Yuka contacted her and asked her to cover for her and the Ishiyama gang, the third time during a scene in a public bath during their field trip to Okinawa, and the fourth and most recent time after the defeat of Satan and Fuji.