Kyoka Jiro/Synopsis

History
Kyoka was born from Kyotoku and Mika Jiro, a couple of a composer and a musician. She inherited her mother's Quirk, Earphone Jack.

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.

U.S.J. Arc
When actual villains invade, 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 the air-headed 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 League of Villains is over.

U.A. Sports Festival Arc
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.

Vs. Hero Killer Arc
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: Jamming Way, causing Denki to reply that her idea was good, as it references the intellectual: Hemmingway. But Kyoka revealed she was just using that name as a means to make fun of Denki, leaving him disappointed. 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.

She interns under Death Arms. She later helps with a hostage situation.

The workplace training comes to an end and Kyoka returns to U.A. After Foundational Hero Studies is finished, Kyoka catches up with Tsuyu and Mina and she is amazed by Tsuyu's activities. She is among the students bearing witness to the gamma race, where she and Momo count Izuku out since his quirk has repercussions. 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.

Final Exams Arc
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.

Forest Training Camp Arc
Due to a shopping center incident, where Izuku had an encounter with Shigaraki, 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 summer camp, they are informed that the new destination will be a mountainous region, owned by the professional Hero Team, the Wild, Wild Pussycats, where they will undergo reinforcement training to strengthen and upgrade their Quirks which will also allow Class 1-A to obtain their temporary licenses. Class 1-A’s bus stops for a restroom break, where they meet Pixie-Bob and Mandalay, who challenge the students to reach base camp past the forest in three hours. Then, all Class 1-A is forcibly thrown into Beast's Forest by Pixie-Bob's Quirk.

To reach their destination, they must traverse the forest, which is inhabited by dozens of hostile earth monsters created by Pixie-Bob. The Students work together to fight their way through the forest. To help her classmates, Kyoka, along with Mezo, use her Quirk to detect the location of the approaching beasts. The journey through the forest to the Cabin takes them around eight hours before finally arrive at the facility, battered and tired. Class 1-A fetch their luggage from the bus and put it in their rooms, and later go to the dining hall and the Pussycats serve dinner.

The next morning, 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. She trains to increase the quality of sound from her quirk by strengthening her Earphone Jack by constantly hitting a rock with the jacks of her earlobes. Afterward, Class 1-A and 1-B are tasked with cooking for themselves. During dinner, Kyoka punches Hanta for making an unfortunate comment about Momo’s Quirk, saying that her ability to create things from her body after eating is like pooping.{ref|chap = 72|ep = 40}}

During the third day of the lodge trip, while Classes 1-A and 1-B are undergoing their Quirk-strengthening training, Pixie-Bob announces both classes that tonight they will be playing a game, a test of courage. Kyoka does not like this idea because she hates scary things. Later, that night, Kyoka is paired with Toru, being the third pair to enter the forest where the test takes place.

At that moment, the Vanguard Action Squad attacks the training camp, filling the forest with poisonous gas. Kyoka and Toru are unconscious because of the gas, being later found by Momo and Yuga. Momo had created several gas masks, and placed two on the faces of her classmates to protect them. After this, Momo asks Yuga to take the unconscious Kyoka and Toru back to the facility while she leaves to help, while she looks for the students of class 1-B.

Kyoka and Toru are hospitalized because of the gas, not knowing that the Vanguard Action Squad members manages to kidnap Bakugo.

Hideout Raid Arc
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.

Provisional Hero License Exam Arc
The day of the License Exam, Class 1-A goes to the place where the tests will take place and here they meet other students from different schools; the organizer of the exam explains to all the participants the rules of the first test, giving all the targets and informs the students that they will have to insert particular balls in the opponents' targets in order to qualify.

When the first trial begins, all the opposing students are thrown against the students of the U.A., who find themselves having to defend themselves against a large number of attacks; Jiro deflects balls coming from the subsoil with her new special move Heartbeat Fuzz. However, a boy from an opposing school uses his quirk to divides the U.A. students.

After the attack, Jiro regroups with Asui, Shoji and Yaoyorozu. In the city area the go to a building with an observatory deck to located more classmates. With no luck, Jiro uses her Earphone Jacks on the wall and informs them that she hears four people coming. She soon realizes that they aren't stopping on any floor but coming directly towards them. Suddenly, Jiro gets hit by a high-volumed speaker playing music against the wall. The group soon realize it's a coordinated attack. The windows are shattered, Asui and Yaoyorozu suspect the opponents are waiting for the right time to strike. Jiro impulsively prepares her super move but is countered and her left ear and arm amp get damaged by an aim quirk.

Seiai Academy continues their plan by freezing the air conditioner. Jiro suggest creating an electric heater but Yaoyorozu says that won't work because the enemy mostly have control of the electricity. Jiro also suggest creating bomb but Yaoyorozu says that won't work either due to the unpredictable damage it will cause. Yaoyorozu comes up with a plan and creates four headphones and a large amp. Everyone puts on the headphones and Jiro connects her undamaged Earphone Jack and creates a sonic attack. The sound force rattles Jiro's body but she holds it in.

After a successful counter attack all of the Seiai Acedemy group is immobilized except Saiko Intelli. Intelli grabs Yaoyorozu and takes her back to the room Yayorozu had just escaped. Jiro and the other two come to her aid and save Yaoyorozu. Intelli questions why they didn't just leave Yaoyorozu to fail but Jiro states class 1-A sticks together.

They make it back to the refreshment area, where they met up with Todoroki and discover that they're the only ones who have passed so far from their class. Minutes later Bakugo, Kaminari & Kirishima arrive, where Jiro comments that Kaminari probably slow downed Bakugo. After awhile the rest of class 1-A pass the first qualifier test.

The qualifiers are informed of the imminent start of the second test, in which the students will have to save the largest number of fake victims in a given period of time. Jiro uses her quirk to locate victims during the second test. At the end of the trial, Kyoka and her friends are shown the results and the girl is happy to see her name on the list of those who received a Hero License.

U.A. School Festival Arc


Kyoka is convinced by her classmates to do a music theme for the U.A. School Festival.

In Class 1-A's Heights Alliance, Tenya Iida is busy helping plan Class 1-A's 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. Class 1-A's performance ends up being a huge hit with Kyoka as the main vocals and playing guitar.

Joint Training Arc
Shota Aizawa and Vlad King hold a Joint Training Battle between their classes during the early days of winter. Each class chooses lots to split into five teams of four. As the teams are set, Kyoka is placed with Katsuki Bakugo, Rikido Sato, and Hanta Sero, and they will face Class B's team of Yosetsu Awase, Setsuna Tokage, Kojiro Bondo, and Togaru Kamakiri at Round 4.