Oboro Shirakumo/Synopsis

History
On his way to start his second-year at U.A. High School, Oboro found a cat that Shota Aizawa left an umbrella over. He takes the cat and the umbrella with him to class, where he arrives through the homeroom class window using a cloud created with his Quirk. He gets in trouble with his teacher, who insists he use the door like everyone else.

Soaked from the rain, Oboro interrupts roll call and to ask if anyone had a towel, although it was to no avail. He also asked Shota if he dropped his umbrella and, when he affirmed, handed it back to him.

Since his clothes were wet, he decided to change into his gym attire in front of everyone. This caused commotion among his classmates, so he used a cloud to censor himself. Oboro pulled out the cat he rescued earlier from the rain, which is met with adoration from his classmates. He allowed roll to continue after getting dressed, and placed the cat on a cloud pillow.

Class 2-A's homeroom teacher begins by reminding students that most second-years do work studies during summer vacation to get a taste of what the world of a Pro Hero is like. Oboro along with Hizashi and Shota are reminded they have yet to assign themselves to an agency.

Oboro and the rest of his class gear up for Joint Exercises with Class 2-B that consist of Battle Training, Rescue Training, and Entertainment Lessons. He excels in each exercise.

A few days later, Oboro's teachers discuss if he has any chance of landing an agency. His homeroom teacher says he doesn't have the grades, but makes up for it with a positive attitude and wherever he does goes, he will manage at his own pace.

After school, Oboro is on the roof top with Hizashi, Shota and the cat he rescued. Oboro is eating sushi, when the trio discuss the practical usages of Shota's Quirk, where Hizashi suggest he should go the battler route so he can fight Villains on even terms. Oboro comments that Quirk matchups can make or break fight. Shota replies back to them he's not much of a fighter and what would he do against heavy brawlers. Shota explanation continues why and gets distracted when Oboro is caught almost feeding the cat sushi. Shota tells Oboro not to give him human feed, and gives him some school milk instead. Shota reminds him that animals aren't allowed at school where Oboro responds he'd feel worse if he let him at home all day.

The trio and cat time on the rooftop is interrupted when third year Nemuri spots them having lunch. She admires the "youth" for breaking the rules and being up there. Oboro ask why she is here, and she explains she was coming back from her Work Study and needed to do some paperwork at school. The roof is one of Nemuri's favorite places which Oboro is happy to learn she's also a rule breaker like them. The trio look at Nemuri, when Shota ask if their is more to hero costume, if it has some high-tech material invisible to idiots. Oboro oblivious to the joke, excitedly is happy to be an "idiot". Nemuri explains the functions of her costume, which just leaves Oboro admiring her beauty.

Nemuri stops talking about herself and spots the cat Shota is holding. Oboro explains him and Shota are taking care of it when Nemuri says you really shouldn't have animals at school and swipes the cat away. Nemuri ask the boys the cats name, with no luck. She ask each of them their favorite food, Oboro says "sushi" and it's decided that will be his name. Oboro tells her they need to find a home for him. Nemuri tells the trio she can't because she's expecting to move after graduation and it's harder to get married as a single cat owner. Nemuri says she'll have him temporally until the trio find him a proper home where Oboro states Nemuri will end up keeping him.

Next day on the roof Shota and Oboro are hanging out on the roof. Oboro says if handing off Sushi was the responsible thing to do while Shota says he will be in good hands with Nemuri. Oboro says they weren't in no condition to take care of him and begin talking about Work-Studies. Hizashi was assigned a battle-oriented one leaving them the last two without one. Nemuri suddenly comes from the roof top door and spots the two. They thank her for taking care of Sushi and she shows them a clip of him from the morning. Disturb by Sushi's bathroom video, they ask if thats the only reason she came up. Nemuri states she knows perfect place for little ones with nowhere to go, and tells her boss will take anyone and invites them two to join her.

Oboro and Shota accept her offer and begin their Work-Studies with His Purple Highness. A day on the field, a robbery is happening when Oboro and Nemuri enter the scene. Nemuri says Team Purple Revolution has arrived forcing the Robber Villain to use his Smoke Quirk. While the smoke is spreading, the Villain starts to escapes and Oboro begins to chase after them. Nemuri stops him and says the smoke could be toxic and they should prioritize evacuating the citizens. Oboro yells at Shota to stop the villain, but the smoke easily counters his Erasure, and His Purple Highness has to come to his aid.

After the villain escapes, His Purple Highness gives his trio feedback. Oboro is praised for his quick reaction without hesitation and good judgement. Oboro might be inexperienced but will grow from this. However, His Purple Highness criticizes Shota, but not for arresting the villain, but for his gloomy face. Mr. Purple advises him to smile more to transmit confidence and hope to folks in trouble.

Later that evening, Oboro and Shota are in the locker room. Shota is thinking about Mr. Purple's advice, but he is gloomy over letting the Villain escape which Oboro reassures him just to keep smiling even if you screw up. Shota receives texts from Nemuri of Sushi making him smile where Oboro points out his big happy smile.

Oboro now partly dressed ask Shota what would he do against the Villain if he encounters him again. Shota is slumped and doesn't know what he can do because the smoke irritates his eyes the closer he is and if he's to far away he can't use his quirk. Oboro knows it's a bad matchup even for him, therefore, suggest lending his goggles to Shota can get up and close.

A few days later, while patrolling Shota spots the same Villain again. Thanks to Oboro's goggles, Shota is able to advance closer, and temporally erase the Villain's Quirk. The Villain angrily attacks Shota but manages to dodge when suddenly Oboro jumps from his cloud and subdues the Villain with his quarterstaff. Oboro and Shota successfully immobilized the Villain and our victorious. His Purple Highness congratulations them both on their teamwork. Oboro and Shota smile triumphantly while the bystanders praise them for their work.

A new semester begins, Class 1-A and 1-B will be having Two on Two Battle Training together. Hizashi notices Shota has added Oboro's signature googles to his hero costume. Oboro happily tells Hizashi that their marketing themselves as a duo, but Shota disagrees and it was the for the sake of protecting his eyes and use of his Quirk. Sensoji interrupts the conversation that they stole his eye protecting idea. Oboro laughs it off.

The Battle Training teams are being selected when Oboro suggest that since Shota and him our doing their Work-Studies together they can team up. Class 1-A homeroom teachers agrees and thus Hizashi and Sensoji our paired as well. Before the two duos go against each other, Sensoji demands Shota to hands his googles over if they lose. Oboro accepts and wagers their googles against Hizashi and Sensoji shades. Oboro tells Shota the goggles symbolize their friendship and that they gotta defend them.

The matchup begins when Sensoji rushes in and uses Blast against Oboro and Shota. Shoto and Oboro dodge, where Oboro counters using his Super Move Cloud Cover to temporally cover his opponent sight. Oboro's clouds surround the battle field and Sensoji is about to blast all the clouds away when Shota comes from behind and erases his Quirk. With no way to defend himself Oboro lends the final blow with his quarter staff. Oboro and Shota our victorious. The wager is called off by Shota, causing Sensoji to storm off. Class 1-A teacher tells Oboro and Shoto they play off each other technical Quirks and to keep it up.

Later, Oboro is hanging out with Shota when Hizashi showcases his new googles to match the other two. Oboro happily once again now says we can sell themselves as a trio. Shota thinks Hizashi is coming to Purple Agency and Oboro corrects him that he's talking about the future, that the three of them can start their own agency. Hizashi and Oboro would start the combat and Shota would be the edge in battle to allow them the final blow. Nemuri shows up and admires the youths bantering. Oboro adds her into the agency now including all of them. Nemuri declines and states she rather be independent with young men waiting on her. Oboro states he wouldn't mind waiting on her and would later give her a pair of googles.

A week later, Oboro is patrolling Tasomiya Ward with Shota. Oboro creates a cloud to lend a ride for a group of nursery kids. Shota guides them and make sure they group looks both ways before crossing. Oboro comments that he's a natural with kids and suggest he should work at a day care or be a school teacher but Shota disagrees. The duo and kids say their goodbyes.

Oboro says Shota is observant and that he overthinks. Oboro believes Shota needs to stop psyching himself out and that he can do anything if he puts his mind to it. Shota doesn't believe he's good enough to work at a day care or be a teacher.

The conversation is interrupted when Nemuri gives an order to start evacuating the area because a powerful Villain is causing havoc. The duo run back to the kids, where Oboro creates a cloud once again now to guide them to safety. Gravey comes into their view causing them to panic. His Purple Highness comes in, to buy them some time so they can focus on the kids. Due to Gravey's Quirk, he releases Hizashi's Voice and Sensoji's Blast onto the city causing destruction. Rumble starts falling on the kids, when Oboro creates a cloud above them to shield them. Due to protecting the kids, Oboro is left defenseless and gets crushed by the rumble. Shota screams for Oboro with no response causing the kids to cry.

Shota faces Garvey head on, hearing Oboro's voice guiding him. Shota successfully defeats the Villain, and yells that "I did it!". Shota is being praised for his action when he interjects and say it was a team effort with his partner, Oboro, cheering him on. Shota asks Nemuri how Oboro's wounds are looking but she doesn't answer. Thinking the worse Shota tells her that he should be taken to the hospital immediately.

Nearby, Hizashi and Sensoji spot Oboro's speaker and pick it up. They notice it's broken when Shota says that can't be true. Shota tells them Oboro voice was cheering him on the entire time, but Sensoji tells him it was likely he was giving himself a pep talk and imagine it was Oboro. Shota brushes Sensoji comment off and believes it was his actual voice. Shota approaches the rumble where Oboro was knocked out and sees Oboro's body bag covered in blood.

After his body is removed from the area, Nemuri tells Shota and Hizashi they should get inside. Hizashi tells her the rain fits the mood they're in and not to worry. Shota remembers all his memories with Oboro, and with Hizashi by his side they mourn the loss of their friend.

Joint Training Arc
After the U.A. faculty conference, where Hitoshi Shinso was officially admitted to the Hero Course, Present Mic brings Oboro up to Shota as they are walking down the hallway.