Tsuyu Asui/Synopsis

History
Before starting at U.A., Tsuyu's mother and father had to travel for work often, which gave them little time to raise their young children. Tsuyu was left with the responsibilities of raising Samidare and Satsuki, such as making dinner for them. Although it was tough raising her younger siblings, Tsuyu still found her life to be wonderful.

Two years ago before starting at U.A., Tsuyu's hero studies at her middle school piled up and she didn't have much free time for herself. Tsuyu's busy schedule, as well as her frog-like appearance, made it difficult for her to make friends. During her time at middle school, there was a student who started stalking her named Habuko Mongoose, who also had difficulty making friends. Habuko often used her Quirk, which paralyzed whoever she looked at for three seconds, on Tsuyu. Despite this, Tsuyu wasn't bothered by Habuko's stalking because she could understand her as they were both lonely.

One day, Tsuyu mustered up the courage and finally asked Habuko to be friends. Habuko was surprised and touched by Tsuyu's kindness, before happily agreeing to be friends with Tsuyu. Eventually, Tsuyu and Habuko graduated from their middle school, but went to different high schools though they kept in contact.

Two years later, the day after U.A.'s semester began, Tsuyu receives a message from Habuko which states that she made new friends at her new high school and next time she will introduce them to her. Even though they ended up going to different high schools, Tsuyu notes that she will always be friends with Habuko. Tsuyu decides that, like Habuko, she will make lots of friends at her new high school as well.

Quirk Apprehension Test Arc
Tsuyu first appears alongside the rest of Class 1-A on the first day of the term. Shortly after the start of class, Class 1-A is brought to the exercise grounds by their homeroom teacher: Shota Aizawa. He informs the class that they must all undertake a Quirk Apprehension Test and whoever comes in last place will be expelled immediately.

When Tsuyu takes part in the 50 meter dash, she races against Tenya Iida, who finishes before her due to the speed of his Engine Quirk. She finishes the race in 5.58 seconds and eventually places thirteenth overall in the class. Tsuyu is then seen discussing with rest rest of the class about the kind of man Mr. Aizawa is.

Battle Trial Arc
Tsuyu is paired with Fumikage Tokoyami for the combat training. After the first battle trial, All Might grants Tenya Iida the most valuable honors. Tsuyu questions this since Izuku Midoriya and Ochaco Uraraka were the victors. Momo Yaoyorozu explains why. Once training finishes, All Might gives the class some positive reinforcement. Tsuyu thanks him for this because she feels like their homeroom teacher is quite the opposite of positive. When Izuku returns to class from the nurse's office, Tsuyu introduces herself to him as "Tsu". She along with Ochaco and Mina are seen together watching Midoriya and Bakugo talking outside of school. Tsuyu tells Ochaco that she wonders what's going on.

Unforeseen Simulation Joint Arc
While deciding who should be class president, Tsuyu mentions that Tenya's voting system may not work since the class hasn't known each other long enough. She votes for herself to be president but Izuku and Momo end up winning the honors. Later on, Shota announces to the Class that they will partake in rescue training at an outside facility. Tsuyu mentions to Eijiro Kirishima that she's excited to show off her skills in the water. Tsuyu receives her hero costume and chooses to leave her goggles behind and boards the bus.

During the bus trip to the outside facility, Tsuyu tells Izuku that his Quirk reminds her of All Might. However, Eijiro argues that Izuku's Quirk injures him while All Might's does not. Eijiro goes on to say that Katsuki Bakugo and Shoto Todoroki have the most pro-worthy Quirks. Tsuyu replies that Katsuki's too angry to become a popular pro, causing him to yell at her and prove her point.

Class 1-A arrives at the Unforeseen Simulation Joint, where they meet the Space Hero: Thirteen. Thirteen explains she developed the U.S.J with the focus on training future heroes on using their Quirks to help others. Suddenly during Thirteen's speech, real villains invade the facility through a warp gate.

Shota fends off the villains on his own and leaves Thirteen to evacuate with the class. They prepare to escape, but they are cut off by the villain Kurogiri. Katsuki and Eijiro attack him, but end up dealing no damage. Kurogiri responds by warping the class to the various areas in the U.S.J.

Tsuyu, Izuku and Minoru Mineta are warped to the shipwreck zone where they are met by villains. Izuku is nearly killed by a fish-like villain underwater, but Tsuyu rescues him by kicking the assailant in the face. She uses her quick swimming skills and her tongue to swiftly bring Izuku and Minoru out of the water an onto the boat. Izuku thanks her for saving his life and she reminds him again to call her "Tsu". They discuss the villain's plans and Minoru mentions that the villains can't kill All Might. Tsuyu argues that the villains likely have a plan in mind and that they need to focus on surviving. The villains in the water start rushing towards the ship. Minoru panics, but Izuku encourages his allies to be heroes because it's up to them to save All Might now.

Tsuyu and Izuku deduce that the villains must've collected information on the U.S.J and gathered villains who would have advantages there. However, they also figure out that the villains likely have no idea what the students' Quirk and skills are. While Tsuyu and her allies strategize and share information on their Quirks, one of the villains uses an aquatic Quirk to cut the ship in half. Minoru starts freaking out as the ship sinks and Tsuyu questions whether the hero track is right for him. Izuku remains clam and creates a plan for them to escape.

Izuku jumps from the ship and uses a Delaware Smash on the water to create a giant shockwave. On his signal, Tsuyu grabs Minoru and jumps from the ship. She grabs Izuku with her tongue while Minoru uses throws sticky spheres from his Quirk at the villains. The aftermath of the shockwave causes the water to rush back to the middle, trapping the villains there because of Minoru's Quirk. As they escape the shipwreck zone, Tsuyu commends her allies by telling them they did an amazing job.

As they leave the water, Tsuyu asks Izuku to stop muttering and second-guessing their plan as he complies. At first, they agree to escape towards the exit, but Izuku decides they should help Shota against the group of villains in the central plaza. They soon arrive there to find Shota facing off with Tomura Shigaraki, the villain's ringleader. Exhausted from fighting, Shota ends up at the mercy of Tomura and his super-powerful ally: Nomu. Tsuyu, Izuku and Minoru watch in horror, but they notice Kurogiri tell Tomura one of the students escaped. They assume the villains plan to escape, but Tsuyu admits to Izuku that she has a sour feeling about this.

Just then, Tomura suddenly decides to attack the group and nearly destroys Tsu's face. Fortunately, Shota uses his Quirk in time to stop Tomura for the time being. Izuku uses the opening to attack Tomura in order to save Tsu, but his smash attack is nullified by Nomu's swift defense of Tomura. Nomu attacks Izuku and Tsu moves to save him, but they are all rescued by the arrival of All Might.

All Might grab Shota and entrusts his unconscious body to the students. Tsuyu, Minoru and Izuku carry him towards the exit until Izuku rushes back to support All Might. Following the battle with the League of Villains, Class 1-A meets up outside the facility and are debrief by Detective Tsukauchi. Yuga Aoyama tells Tsuyu it's a secret where he got warped to. She ignores him and asks the detective about the condition of Shota and Thirteen.

U.A. Sports Festival Arc
When classes resume for Class 1-A, Mina asks Tsuyu who she believes will teach the class. Tsuyu replies she has no idea since Shota is still in the hospital recovering from his injuries. She's proven wrong when Shota greets the class covered in bandages. He uses the class time to explain that the U.A. Sports Festival is fast approaching. During lunchtime, Tsuyu's classmates express their excitement in anticipation of the festival. Tsuyu takes notice of Tenya's dancing and compliments him. The most excited person appears to be Ochaco, who proclaims to the class that she'll do her very best. Tsuyu and her others cheer her on as she yells about doing her best.

Tsuyu uses the two weeks before the festival to train. She uses one of the school's indoor pools to practice by catching toy fish underwater using her tongue. When the day of the sports festival arrives, Tsuyu listens to Shoto's proclamation in Class 1-A's waiting room. Afterwards, she accompanies her class for the opening ceremony.

The first event is revealed to be an Obstacle Race. When the race begins, Shoto tries to freeze everyone trailing him. Tsuyu manages to avoid the ice and eventually reaches the second leg of the race: "The Fall". She quickly traverses through the obstacle by balancing herself across the tightropes. Then Tsuyu carefully makes her way towards through the minefield rather than trying to jump across it. She takes notice when Izuku detonates various minds in order to propel himself into first place. Tsuyu manages to finish the Obstacle Race in thirteenth place, qualifying her for the second event: The Cavalry Battle.

Tsuyu teams up with Minoru and Mezo Shoji for the Cavalry Battle. She and Minoru use their compact bodies to hide underneath Mezo's tentacles while riding on his back. When Mezo attacks Team Midoriya and Team Tetsutetsu, Tsuyu uses her tongue to try and steal their points. They are both able to avoid her, so she commends Izuku's impressive moves.

Soon after, Minoru's points are mysteriously stolen and he cries over it. Tsuyu admits she wouldn't have team up with him if it wasn't for his clever plan. She adds that like him, she has no idea how Minoru's points got stolen. Mezo goes into attack mode and attacks Team Midoriya and Team Todoroki. Shoto counters their assault by using Denki's lightning to shock and paralyze all teams around them. Then Shoto uses his Quirk to freeze everyone including Mezo in place. Unable to move, Team Minoru doesn't acquire enough points to move onto the finals. When the event commences, Tsuyu states he's frustrated by her failure but congratulates Mina for moving on.

During the intermission between events, Denki and Minoru manage to fool the girls of Class 1-A into dressing up as cheerleaders. Most of the girls appear to be upset about it, but Toru suggests they roll with it. Tsuyu responds by telling Toru that she's got cheerleading skills. They are all later embarrassed when Mashirao asks them why they're dressed up.

Tsuyu watches the finals from the stands and cheers on Mina during her match with Yuga. Before the bout between Ochaco and Katsuki begins, Tsuyu comments that it will be the match that will be the most difficult to watch. Their match starts with Katsuki blasts Ochaco at point blank, and Tsuyu notes that Katsuki doesn't plan on holding back.

Shoto eventually defeats Izuku in the second round and injures him. Tsuyu, Ochaco, Tenya and Minoru go to Recovery Girl's office to check on Izuku's condition. However, they're forced to leave because Izuku is about to undergo surgery. When Fumikage easily defeats Mina, Tsuyu comments that his dark shadow is amazing. Then she notices Ochaco worrying about Izuku and reassures her. Once the festival concludes, Tsuyu and her peers attend the closing ceremony of U.A.'s Sports Festival. They are all given the following two days off to recuperate.

Vs. Hero Killer Arc
When classes resume at U.A. High, Tsuyu notes that Shota has recovered from his injuries and isn't wearing bandages anymore. He informs the students that they will use the class to choose their hero identities. Tsuyu doesn't receive any offers from Pro Heroes, but she and all of her peers will still need to intern with real heroes. Midnight joins the class to approve the student's code names. Tsuyu presents her chosen hero name that she thought of since elementary school: Rainy Season Hero "Froppy". Midnight commends her for her choice and tells the class to use Froppy as an inspiration. Tsuyu's peers cheer the name Froppy as praise for changing the mood of the class.

Once the class finishes formulating code names, they are all given a list of Hero agencies and have two days to choose which office to intern with. After class, Minoru mentions he wants to intern with Mount Lady. Tsuyu comments that he's having perverted thoughts. She notices Izuku muttering at his desk and tells him he must be thinking hard about where to choose.

Two days later, Tsuyu and her class meet at the train station. Shota reminds them to remain formal and not to lose their costumes before seeing them off to their workplaces of choice. Tsuyu chooses to intern with the Pro Hero Selkie and his sidekick Sirius aboard the Oki Mariner.

On the fifth day of internships, Tsuyu is ordered to clean the deck of the ship. Once she's done, Tsuyu and Sirius share a drink. Tsuyu admits the internship has been boring and Sirius agrees because her internship was the same way. Sirius goes on to encourage Tsuyu by telling her she discovered what was important about being a hero during her time.

Tsuyu asks her to explain, but Sirius claims Tsuyu will find out on her own. Selkie finds them both sitting down and scolds them for not doing work. Sirius corrects him, stating that Tsuyu finished her chores and is being supervised properly. Selkie apologizes and tries to look cute. Sirius berates him for it, but Tsuyu actually finds him adorable. Then one of his crew members informs Selkie that the Oki Mariner has received a mission from the coast guard.

The Oki Mariner departs to investigate a trade ship that had its cargo stolen by stowaways. Tsuyu deduces herself that the stowaways got away from the Coast Guard themselves. Selkie takes to the water himself to search for the ship while Tsuyu and Sirius search via radar during the night. Their search turns up empty, but the crew receives a message that a boat thought to belong to the stowaways is in their general area after escaping another pursuer. Selkie returns to the ship after confirming the location of the boat and they eventually happen upon it. Selkie boards the ship without Tsuyu, much to her dismay.

Onboard the fishing boat, Selkie and a couple of his crewmates are trapped inside after being fooled. Using her Quirk, Sirius hears Selkie tell her this boat was a decoy and they must pursue the real stowaways. They find another boat hiding in the shadows of a large rock and board it. They are immediately attacked by the criminal ringleader: Innsmouth.

Innsmouth wraps his tentacles around Sirius and threatens to crush her if Tsuyu doesn't tell her superiors to call off the search. Inspired by Sirius' words from earlier, Tsuyu gives away their location, angering Innsmouth. The villain attacks and Tsuyu jumps around to avoid his blows. She tries to use her tongue to secure Sirius, but Innsmouth grabs it and slams her into one of the rocks.

Tsuyu is pinned down, but just Innsmouth prepares to finish her off, Selkie arrives to save the day. Innsmouth blinds him, but using his Quirk, he echolocates and defeats the villain. Afterwards, Tsuyu tells Sirius she's discovered whats important about being a hero. The criminals are all arrested and the coast guard thanks Tsuyu for her involvement. Selkie also mentions to them that he believes Froppy will one day become a great hero.

Once the internship week concludes, Tsuyu returns to U.A. High. Back in class, Tsuyu discusses her internship experience with Kyoka and Mina. They find her run-in with drug smugglers very cool. Tsuyu then asks Ochaco about her experience, to which Ochaco replies was very enlightening. Tsuyu notes that Ochaco awakened her fighting spirit with Gunhead's agency. Later on, Class 1-A participates in a rescue training race during Basic Hero Training class. Tsuyu agrees with Ochaco that Tenya will win out of the first group. However, she is surprised and amazed when Izuku shows off his new moves and better control of his quirk.

Following class, Tsuyu changes back into her uniform in the girl's locker room. Minoru tries to peep using a hole in the wall, but Kyoka stops him.

Final Exams Arc
One week prior to final exams Tsuyu sits at lunch with Izuku, Shoto, Tenya, Toru, and Ochaco. They discuss both the written and practical portions of the exam. Neito Monoma interrupts when he bumps into Izuku and taunts the class about his run-in with the hero killer. Itsuka Kendo stops him and shares information about the practical exam, believing it will be combat against villain bots. Following the written exams, Class 1-A meets up with the teachers at the central plaza of the Practical Exam Arena.

Shota and Nezu inform the class that rather than fighting villain bots, the class will be paired up and matched up against one of the teachers. The students will have thirty minutes to handcuff the handicapped teacher or flee through the escape gate. Tsuyu is paired with Fumikage against Ectoplasm for the second battle. During Rikido and Eijiro's match with Cementoss, Tsuyu and Fumikage strategize together. When Cementoss defeats them, Tsuyu is surprised Eijiro was defeated so easily. She and Fumikage make their way to the center of a labyrinth where they are met by Ectoplasm and his many clones. He warns them that the teachers are doing their best to utterly crush the students.

Seeing that they are at a disadvantage, Fumikage orders Dark Shadow to throw Tsuyu onto the next floor. Then Tsuyu grabs Fumikage with her tongue and throws brings him up to her level. Ectoplasm comments on their nice synergy. Together, Tsuyu and Fumikage run through the labyrinth while trying to find the escape gate. They are met with wave after wave of Ectoplasm's clones. Fumikage does the bulk of the fighting himself, but whenever he's overwhelmed, Tsuyu is there to support him. They escape to higher floors.

They work together to defeat about twenty-eight clones and reach the final section of the building where they can see the escape gate and Ectoplasm's real body. Ectoplasm commends them for making it past his clones and spawns a giant one to stop them using his Giant Bite Detention technique. Fumikage yells for Tsuyu to avoid it, but they are both trapped outside the clones body.

Ectoplasm tells them only he can release his clones and asks what they plan to do now. While Dark Shadow fights with Ectoplasm to escape, Tsuyu reveals she swallowed the handcuffs given to them prior to the practical. She gives it to Dark Shadow without Ectoplasm noticing and they clash one final time. Although Dark Shadow is defeated, Ectoplasm's leg is cuffed in the exchange. The duo pass the exam and Ectoplasm congratulates them on a wonderfully clever plan.

Tsuyu accompanies other in watching Izuku and Katsuki's battle with All Might. Following the conclusion of the exams, Class 1-A returns to their homeroom class as scheduled. Shota informs the class that they have all passed the written exam and everyone will attend training camp over the summer. Tsuyu's peers decide its a good idea to go shopping at the Kiyashi Ward Shopping Mall to buy necessities for the camp.

Forest Training Camp Arc
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. They meet two females who Izuku excitedly introduces as the Wild, Wild Pussycats. The heroes tell them the area is part of their domain; they have three hours to reach the base of the mountain using their Quirks as they please and those who don't arrive there by 12:30 pm won't 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 Pixiebob 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. The journey through the forest to the Cabin takes around eight hours. Class 1-A arrive at the facility, battered and tired. It is now 5:20 pm in the evening. Pixiebob 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.

When Shota authorizes Classes 1-A and 1-B to fight back against the villains, Tsuyu and Ochaco are already facing Himiko Toga.

A few moments earlier before the Bakugo Escort Squad was formed, Tsuyu and Ochaco are fighting Himiko Toga who managed to slightly wound Ochaco’s arm. Himiko notes that her Quirk requires her to make big wounds in order to suck her targets’ blood. However, thanks to her machine, her Quirk’s weakness is compensated by the machine’s ability to drain blood from tiny wounds. Himiko begins to attack, to which Tsuyu responds to by flinging Ochaco away with her tongue. Tsuyu tells Ochaco to run back to the facility and call for help and says that she also plans on retreating with her.

Suddenly, Himiko manages to wound Tsuyu’s tongue with one of her knives. Tsuyu tries running away, only for Himiko to pin her hair to a tree with her machine. Himiko prepares to drain Tsuyu’s blood, however, Ochaco arrives to Tsuyu’s aid which causes Himiko to turn her attention to Ochaco. Himiko attacks with her knife, only for Ochaco to dodge. Ochaco uses the martial arts skills she learned from Gunhead to force Himiko onto the ground.

Straddling Himiko's back, Ochaco tells Tsuyu to restrain her arms. Himiko notes that love stories are fun and uses her machine to stab Ochaco’s leg, who was unable to stop her due to being caught off guard with Himiko’s talking. Himiko begins draining Ochaco’s blood.

Suddenly, the Bakugo Escort Team arrives and sees Ochaco. Himiko stops draining Ochaco’s blood and pushes Ochaco aside, not wanting to engage a large group of enemies and not wanting to die. Himiko retreats with Ochaco wanting to follow her, but Tsuyu stops her due to Himiko’s Quirk being largely unknown. After seeing that Ochaco and Tsuyu are alright, Izuku asks them to join the escort. However, Ochaco and Tsuyu wonder why Katsuki isn’t with them. Mezo, Shoto and Izuku turn around only to find that Fumikage and Katsuki are missing.

Suddenly, a masked villain appears on a tree branch and reveals that he used his “magic” to take Katsuki by turning him into a marble. The masked magician-like villain states that the Heroes don’t deserve someone of Katsuki’s caliber and notes that Katsuki will shine even brighter on the villains' side. Izuku demands that he give Katsuki back.

Tsuyu helps Izuku, Mezo and Shoto by throwing their weightless bodies at Mr. Compress which allows them to reach him. Tsuyu and Ochaco run to the villains' rendezvous point, only to find out that the villains' succeeded in capturing Katsuki.

Two days afterwards, Tsuyu visits Izuku in hospital. She berates Izuku and the others for wanting to break into the villains hideout and save Katsuki, by deeming their thoughts at no better than the villains.

Hideout Raid Arc
Tsuyu watches the broadcast of the battle between All Might and Sensei.

Provisional Hero License Exam Arc
At Ochaco's urgings, Izuku, Tenya, Momo, and Eijiro all meet outside the dorm where they find her with Tsuyu. Tsuyu apologizes for harshly doubting their plan to save Katsuki, as they apologize for worrying her and they manage mend their friendship.

She later participates in the exam and manages to pass, obtaining hero license in the process.

Internship Arc
Tsuyu, along with Class 1-A, is introduced to Big 3 members:Mirio Togata,Tamaki Amajiki and Nejire Hado. Upon introducing themselves, Mirio mentions internships about Class 1-A and challenges them to a fight. Inside Gym Gamma, he manages to defeat the entire Class 1-A alone. When the fight finishes, Mirio explains to them how his internship helped with his Quirk, he says it's an opportunity they can't afford to miss out on.

Following this advice and thanks to Nejire's recommendation, Tsuyu is revealed to be doing an internship with Ryukyu along with Ochaco. They defeat a villain together and use a new combo move called Meteor Fafrotskies. Nejire recommended them to Ryukyu and she accepted. Nejire then tells her that both of them were turned down by the field training teachers. Ryukyu then tells them that the internship will help with their fighting skills and that they might help with "The Case". The Case is to team up with Sir Nighteye's hero office for an investigation.

Several days later, she participates in the police raid against Shie Hassaikai, surrounding the organization's headquarters. While the heroes and the police forcer waited outside, suddenly, the gates smash open courtesy of Rikiya Katsukame, and begins to attack them. Ryuko turns into a dragon, and easily intercepts Rikiya’s punch with her draconian claw. Ryukyu orders her Heroes from the Ryukyu Offices to deal with Rikiya and asks the other groups to move on, while she and her team deal with Rikiya.

Ryuko’s group managed to overpower Rikiya and knock him unconscious. Ryukyu orders the Police Force to restraining Rikiya while Nejire Hado, Ochaco Uraraka and Tsuyu Asui prepare to head after Sir Nighteye's group. Suddenly, Ochaco and Tsuyu along with the Police Force become tired due to Rikiya inhaling their vitality, much to Ryukyu's surprise since she thought she knocked him out. Conscious, Rikiya reveals that the drug he took is kicking in which has enhanced his Quirk and now he can absorb a target's vitality simply by inhaling.

Now larger and stronger than before, Rikiya attacks the Police Force only for Ryukyu to take them to safety. 20 minutes pass and Ryukyu's group is in a standstill against the rejuvenated Rikiya. Only Nejire continues to fight against him.

Suddenly, Izuku Midoriya appears and states that he called reinforcements and that their objective is underneath a nearby crossroad. With this information, Ryukyu hatches a plan, transforms into her dragon form, and charges at Rikiya. With the help of Ochaco, Tsuyu and Nejire, she crashes Rikiya against the point indicated by Izuku, collapsing the crossroad, and causing Ryukyu's group along with Rikiya to fall down into underground, in the middle of the battle between Izuku and Kai. Actually, the Izuku of the surface reveals to be Himiko Toga, who used her quirk to impersonating him.

Izuku manages to defeat Kai and the mission ends in success, Eri is rescued and the organization dismantled. However Sir Nighteye dies hours later in the hospital because due the injuries suffered.