Kyoka is a petite, slender teenager. She has fair skin, triangular onyx eyes, and short purple hair with asymmetric bangs. Her most notable feature is her plug-like earlobes which seem to be able to change length and control at will. Unlike the other students, Kyoka wears a vest over her school uniform.
Her costume consists of a black jacket, long peach-colored shirt with several rips at the collar and bottom, black pants, and boots with stereos in them. She also sports two small, red triangle facial marks just below her eyes, a plain black choker, and white finger-less gloves. Later on, her hero costume gains a set of headphones and two bracelets that double as her amplifiers.
Kyoka has a somewhat pragmatic, unenthusiastic and rude personality which is shown a lot to those she finds irritating, in particular her fellow classmate Denki Kaminari, who happens to be the most common target of her snarky comments. She can also be quite aggressive and may use her Quirk to physically punish people or to keep them in line, notably Denki and Minoru Mineta.
Despite the fact that she comes off as cold and indifferent, Kyoka also has a much more sensitive side, being very defensive and empathetic towards her friends and others. Additionally, she is afraid of horror-based activities and has an aversion to nudity.
Like her parents, Kyoka has a major interest in music (rock, in particular) and owns several instruments which she is able to play to some extent. However, she appeared to be somewhat embarrassed about her interests, mostly due to perceiving them as completely unrelated to heroism, though she has grown more confident over time.
Kyoka also seemed to suffer from certain self-confidence issues in regards to her own body, most likely due to not being as physically developed as the rest of her female classmates.
At a young age, thanks to the influence of her parents, Kyoka developed an interest in music, eventually learning to play several instruments.
Despite her parents desires for her to become a musician, she decided to become a hero instead because she wanted to dedicate her work to others. When she told her parents about her plans, they were happy for her and let her walk her own path.
Kyoka is warped to the mountain area of the Unforeseen Simulation Joint along with Momo Yaoyorozu and Denki Kaminari. Annoyed that Denki is complaining too much, she kicks him into one of the villains, causing the villain to be electrocuted by Denki's Electrification. She then uses her Quirk to protect Denki from an attack by one of the villains. Kyoka plugs her jacks into her boots to launch a sonic attack, causing the villains to block their ears in pain, which gives Momo the time needed to create an insulator sheet. Kyoka and Momo hide under the insulator sheet while Denki discharges a great amount of electricity, defeating the villains while Kyoka and Momo remain unharmed.
However, one of the villains takes an airheaded Denki hostage, forcing Kyoka and Momo to stop fighting back and remain motionless. Kyoka attempts a sneak attack by distracting the villain through conversation, but fails. Fortunately, the villain holding Denki is shot down by Snipe, freeing Denki, with Kyoka rushing to tie up the villain. She is then seen with her class after the battle with the Villain Alliance is over.
After Shota announces that the Sports Festival is approaching, Denki says that he plans to become a Pro's sidekick after he graduates, to which Kyoka states that many people become sidekicks and fail to become real Heroes, to which she thinks that Denki is the kind of person who would become like that, which causes Denki to become crestfallen. Kyoka competes in the Obstacle Race where she places 21st, allowing her to compete in the Human Cavalry Battle. In the Human Cavalry Battle, she teams up with Rikido Sato, Koji Koda, and Toru Hagakure while Toru is the rider. When the Human Cavalry Battle begins, Kyoka uses her Quirk to try and grab Izuku's headband like Tetsutetsu Tetsutetsu told her, but Fumikage uses his Dark Shadow to block her attack. Later in the Human Cavalry Battle, her team charges towards Shoto Todoroki's team, but her team gets zapped by Denki and frozen by Shoto's team. Her team fails to qualify to the next round when her team lost the Human Cavalry Battle.
After Denki and Minoru state that the girls must do the cheering battle as per orders from their homeroom teacher, Kyoka and the other girls of Class 1-A walk out in cheerleading outfits. However, as Kyoka and the girls walk out, they realize they have been tricked. Kyoka then calls Denki and Minoru idiots. During the recreational events, Kyoka is seen sitting still in her cheerleader outfit while watching Mina, Ochaco, Tsuyu, and Toru cheerlead. As the match between Ochaco and Katsuki begins, Kyoka comments that she might look away the entire time. During the match between Ochaco and Katsuki, Kyoka averts her eyes from the match when seeing Katsuki's explosion assault on Ochaco.
Kyoka along with her class watches the closing ceremony of U.A.'s Sports Festival.
Two days after the Sports Festival, Kyoka is in class. During the Hero Informatics period, Class 1-A has to decide on Hero names. Kyoka gives Denki an idea for his Hero name, causing Denki to reply that her idea was intellectual, horrified that she was complimented for her intelligence. Kyoka writes down and shows her Hero name to her classmates. Kyoka reveals her Hero name to be Earphone Jack, the Hearing Hero.
After Class 1-A has finished formulating their Hero names, Kyoka is given a list of 40 workplaces in order to choose a workplace that she would like to train at. On the day of the workplace training, Kyoka is at the train station with her class so that she can go to the workplace of her choice by train.
The workplace training comes to an end and Kyoka returns to U.A. After Foundational Hero Studies is finished, Kyoka is among the students bearing witness to the gamma race. She and Momo count Izuku out since his quirk has repercussions, though they are quickly proven wrong when Izuku shows off his new moves and they are surprised as well as amazed at his better control of his quirk and lead in the race until he trips causing him to lose.
Later on, Kyoka is in the girls' locker room where she uses her earphone jacks to hear Minoru's plan to peek on the girls. Kyoka plugs one of her earphone jacks into the hole which stabs Minoru's eye, stopping Minoru from peeking. Though thanked by the other girls, an embarrassed Kyoka wonders why she was the only one he did not mention.
One week before the end of term test, Kyoka asks Momo to help her study. Throughout the final week before the end of term test, Kyoka studies under Momo's tutoring along with Denki, Mina, Mashirao and Hanta. On the day of the exercise test, Mr. Principal reveals that Class 1-A will be fighting against U.A.'s teachers for their exercise test. Kyoka is paired with Koji and they must face Present Mic in their exercise test.
Koji, Kyoka and Present Mic arrive in an uninhabited city where Class 1-A's test exercise will take place. In the city, Kyoka mocks Present Mic for what she takes as a poor reference, to which Present Mic tells her to be careful with what she says. Present Mic explains the 30-minute test; Kyoka and Koji must either handcuff him or one of them must escape the battlefield within 30 minutes in order to win and pass the test. The test begins.
Kyoka plugs in her Earphone Jacks to try and block out Present Mic's loud voice, but to no avail. Annoyed by Present Mic's loud voice, Kyoka tells Koji to command the nearby animals to attack but Koji is unable to due to Present Mic's voice making the animals wild and as a result, any command he gave would be useless.
Kyoka and Koji manage to get a little closer to the escape gate, but Kyoka notes that Present Mic will be at the escape gate and that no matter what option of victory they choose, a standoff is inevitable. Present Mic uses his loud voice again; Kyoka notes that they cannot get any closer as long as Present Mic is using his Quirk. Kyoka sees an ant and comes up with an idea; she asks Koji if he can control bugs but his terrified reaction indicates that he doesn't like bugs. Present Mic uses his loud voice once again; Kyoka tries to counteract with her Earphone Jacks' but the sound of her heartbeat does not do anything against Present Mic.
Present Mic continues using his loud voice against Kyoka and Koji who are unable to handle it. Out of options, Kyoka asks Koji if he can control insects to which he approves. Kyoka uses her Earphone Jacks to break a rock which reveals dozens of insects, much to Koji's terror. Kyoka tells Koji that she understands his phobia but using the insects to attack Present Mic is the only plan she can think of because their opponent is too strong. Kyoka encourages Koji to follow through with her plan.
After seeing Kyoka's bleeding ears, Koji is ashamed that he is running away from this fight and realizes that he can only continue being at U.A. by overcoming his fear. Koji musters up the courage and commands the insects to attack Present Mic while Kyoka is annoyed he picked that moment to talk. At the escape gate, Present Mic sees that time is nearly up. Suddenly, dozens of insects crawl on Present Mic, who realizes that the insects traveled to him by moving underground; a place where sound is ineffective. Present Mic is paralyzed by fear, allowing Koji to run through the escape gate while carrying an injured Kyoka with him; thus they pass the practical test.
Back at U.A. in class, Kyoka learns that she has passed the written test and will go along with her classmates to the forest lodge which is a boot camp. Kyoka accompanies her class to the Kiyashi Ward Shopping Mall to buy necessities for the forest lodge. At the shopping mall, Kyoka says that she requires a big carrying bag, to which Momo tells Kyoka that she will help her look for it.
The next day after the shopping trip, at U.A., Shota informs Class 1-A that the destination for their lodge trip has been changed and the new destination will only be announced on the day of the event. The first semester has come to a close and summer break has begun.
On the day of the event, Class 1-A boards a bus that will take them to the forest lodge destination. An hour later, Class 1-A's bus stops for a restroom break. However, Class 1-A notes that Class 1-B is not at the rest stop. Suddenly, two females wearing cat-like costumes and a small boy appear; Izuku excitedly introduce the females as the professional Hero Team, The Pussycats. Mandalay explains to Class 1-A that they will be staying at the base of a mountain which is a part of their domain; they have three hours to reach the base of the mountain using their Quirks as they please and those who do not arrive there by 12:30 pm will not be served lunch. Soon, Class 1-A realize that they have already arrived at their destination and their training camp has already begun with The Pussycats being their supervisors. Some of Class 1-A try to leave, but Pixie-bob uses her Quirk to create a landslide of dirt that causes Class 1-A to fall into a forest called Forest of Magic Beasts, which they must traverse to reach their destination. Suddenly, Class 1-A are confronted by a beast; Koji tries using his Quirk to control the beast but it does not work due to the beast being made out of dirt. Izuku, Shoto, Tenya, and Katsuki mobilize and use their Quirks to destroy the dirt beast.
After Izuku, Tenya, Shoto, and Katsuki destroy the dirt beast, Class 1-A begins traversing the Forest of Magic Beasts. However, the journey through the forest to the Cabin takes around about 8 hours. Class 1-A arrive at the facility, battered and tired. It is now 5:20 pm in the evening. Pixie-bob admits that she thought they would take longer to get to the facility; she praises Class 1-A for figuring out her Earth Beasts quickly and easily. Class 1-A fetch their luggage from the bus and put it in their rooms. Class 1-A go to the dining hall to have dinner. After finishing eating dinner, Class 1-A go to the hot springs.
The next day at 5:30 AM, Class 1-A are outside the training camp cabin. Shota greets his students and tells them that they will undergo reinforcement training to strengthen and upgrade their Quirks which will also allow Class 1-A to obtain their temporary licenses.
During the night of the third day, the Vanguard Action Squad attacks the training camp, filling the forest with poisonous gas and fire. Momo runs into Yuga and asks him to take the unconscious Kyoka and Toru back to the facility. Near the Vanguard Action Squad's rendezvous point, Yuga hides behind a bush along with Kyoka and Tooru. Yuga contemplates on what to do because he was instructed by Momo to take the unconscious Kyoka and Tooru back to the facility, but Dabi and Twice’s presence are preventing him from doing that. Suddenly, Dabi spots the bush Yuga is hiding behind, much to Yuga's fear. Dabi prepares to go and check, however, he stops after Twice informs him that they must also call back Nomu since he only responds to Dabi. Yuga is relieved that Dabi did not discover him.
After Katsuki is captured by the Vanguard Action Squad, Kyoka is taken to hospital in the hopes that she regains consciousness. Eventually, Kyoka regains consciousness, recovers and returns home. Shota and All Might visit her house and speak to her parents regarding relocating the U.A students to the dormitories. Kyoka's father is initially hesitant, but Kyoka tells Shota not to worry since her father has already agreed to send her to the dorms since he is actually happy that her daughter will become a powerful hero like All Might after witnessing his fight on TV.
Kyoka was one of the 18 students in class 1-A to pass the Exam and earn her hero license.
Kyoka is convinced by her classmates to do a music theme for the U.A. culture festival.
In Class 1-A's Heights Alliance, Tenya Iida is busy helping plan Class 1-A band and dance performance. Kyoka Jiro suggests club rock and asks if anyone can play instruments such as drums. Denki Kaminari remembers Katsuki having experience in playing drums which Hanta Sero agrees to. Katsuki refuses to as Hanta mocks Katsuki's inability to do so. Katsuki grabs some drum sticks and starts playing the drums proficiently. Katsuki's performance impresses Kyoka who wants him to play the drums. Katsuki begins walking away while expressing his disinterest. Katsuki also expresses his discontent with Class 1-A presenting the band and dance performance as a stress reliever, believing people who sicken him do not deserve his courtesy, and states that all they are doing is indulging the other students. Tenya and Momo Yaoyorozu take Katsuki's views into consideration as Shoto Todoroki points out that Katsuki should not speak ill of them if he has not even partaken in the conversation. Katsuki tells them that they do not fight villains because they enjoy it and likewise they should not consider people's feelings for a band and dance performance; if they are going to do a band and dance performance, they should do it for the sake of it and not to please or help people. Katsuki announces that he will blow everyone away in U.A. with his sound. Kyoka and some of Class 1-A are surprised with Katsuki's willingness to participate; Kyoka also decides to do her best.
Quirk and Abilities
Earphone Jack (イヤホンジャック Iyahon Jakku?): Kyoka's Quirk allows her to plug the jacks that hang from her earlobes into all sorts of things and channel the sound of her heartbeat into them; the vibrations cause havoc inside the plugged objects. Her quirk also allows her to hear very well. She also can plug the jacks into the boots of her costume which have speakers that allow her to shoot sound in a specific direction. Kyoka can use her earphone jacks to catch sounds, giving her the ability to hear across even extremely thick walls. She can use them like whips in combat; stretching up to 6 meters and the sound radius is approximately 12 meters.
- Whip Attack: Kyoka can use her jacks as extremely long-range whips, having enough strength to shatter huge rocks.
- Cancelling (
相 殺Sōsai?): This special move allows Kyoka to block out other sounds.
- Heartbeat Fuzz (ハートビートファズ Hātobīto Fazu?): Kyoka can plug her jacks into the amplifiers on her forearms, slamming the amplifiers onto the floor to finally channel a powerful heartbeat through them that shatters the ground.
Sword Fighting: Though she does not directly use a sword in combat, she has shown to be skilled enough to wield a sword Yaoyorozu had made during the attack on USJ, and hold her own against members of the League of Villains using it.
Musical Talent: Kyoka is able to play the bass, which is her preferred instrument alongside the guitar. She can play other instruments as well, like drums, but only to a limited extent. Her singing voice is described as "husky, but heavenly".
Amplifier Jack: Devices that Kyoka can plug her jacks into, amplifying even further the sound and vibration of her heartbeats. They are worn on both her forearms.
Though the two seem to work well together, they tend to argue quite a lot. Even more likely, Kyoka will tell Denki rude things that will put his mood down. However, Kyoka happens to enjoy Denki's brainless state, finding it uncontrollably funny.
Interestingly, when Denki finds out about her music hobby, and compliments her, encouraging her to embrace her hobbies publicly, Kyoka gets flustered by his praise and rejects his encouragement.
Kyoka and Momo appear to be close friends with each other.
During the Unforeseen Simulation Joint Arc, the two fought villains together with Denki, proving to work well as a team. During the End of Term Test Arc, Momo helped Kyoka to study for the class midterms.
When the class split up to go shopping for the training camp, Momo and Kyoka paired up and went off shopping together. She also has proven to be somewhat defensive of Momo, as she hit Hanta for upsetting her with his distasteful comment about her Quirk.
Kyoka and Koji know the functions of the other's Quirk, and had proven to fight together efficiently. When Koji was afraid to use his quirk by talking to the bugs, Kyoka comforted him by showing him that there are more factors to become a hero, encouraging him to defeat Present Mic in order to pass the test.
- Kyoka's name contains the kanji for "ear" (耳?), "sound/reverberation" (響?), and "incense" (香?).
- Kyoka was the first person in series shown to name her alias after her Quirk's name. The second being Kai Chisaki with his villain name "Overhaul" being the same as his quirk's name along with Hari Kurono's alias being named after his quirk which is Chronostasis.
- Kyoka's rankings in the Popularity Polls are as follows:
- Kyoka ranked 16th in the First Popularity Poll.
- Kyoka ranked 7th in the Second Popularity Poll.
- Kyoka's known U.A. data is as follows:
- Kyoka's hair streaks are drawn similarly to the waves of an EKG, a possible reference to how she uses her earphone jacks to amplify her heartbeat.
- In the preliminary stages of the manga, Kyoka was virtually unchanged from her original design, albeit her hair lacked its signature streaks.
- Along with Tsuyu, Kyoka is the only known example of a character that has the exact same Quirk as one of their parents, in this case she shares her Earphone Jack Quirk with her mother Mika while Tsuyu's whole family has the same quirk.
- (To Koji Koda about using his Quirk to combat Present Mic) "If you do this, we just might win. But there's no time to hesitate, so do it now! You wanna be a hero, don't you?! Then let's pass this test."