Yū has dark brown hair, and pink eyes, various outfits throughout the series but is mostly seen in his Hoshinoumi uniform, which consists of a black jacket and a white under-shirt with a dark blue shirt underneath, black pants, and brown shoes.
As for Happiness, You Did Not Notice he is seen wearing the summer variant of the uniform, which consists of a white shirt, black pants, and brown shoes. After Ayumi's death (The End of the Exodus), Yū wears a dark red hoodie with a red undershirt, blue pants, and brown shoes. During this time he has dark rings under his eyes, implying malnutrition.
Other outfits donned by Yū include his Hinomori High School winter uniform, which consists of a white blazer with a turquoise tie and white undershirt, grey pants, and black shoes. Interestingly, the uniform of his middle school is identical in design to his Hoshinoumi uniform, except that it is turquoise in color.
While he uses his original ability, his irises become lime green and his pupils become light teal. When he uses telekinesis, a purple glow surrounds his body. When he uses time-leap, his eyes glow bright blue with white lines spinning within the irises.
After the events of Charlotte, during which Yū's right eye is slashed by an enemy assailant's knife, a scar is clearly visible where he was injured. Therefore, he wore a medical eye-patch while he was hospitalized.
During the second half of Memories to Come, Yū is seen wearing a black coat with a hoodie and rolled up sleeves, a red undershirt, blue pants and black shoes. He also wears a black watch on his left wrist. He is noticeably taller, his hair is longer and almost completely covers his scarred eye.
Yū, at the start of the series, is a selfish, arrogant and narcissistic boy, who misuses his ability on a daily basis. It is implied that he is an academically poor student and hence needed to cheat to achieve top-ranked grades; whether this is accurate or he simply saw it as easier than having to study is unknown, but Nao implies that his standardized test scores are low. Despite this, Yū is clearly intelligent, being able to devise carefully calculated schemes to achieve his devious goals. He is also able to calmly analyze situations, shown during the baseball game in Moment of Earnest. Furthermore, considering the fact that he is able to memorize the answers of the smart students under 5 seconds he shows the potential to be exceedingly diligent however he does not put his academic abilities and talent to use. While a master of his own crafts, Yū isn't the best at socializing with others and is quite rude at the beginning of the story. He acts differently only when talking with his younger sister, Ayumi, with whom he tones down his personality and becomes more open and brotherly. It is also implied that he has a sister complex. While masquerading as a model student, he hides his narcissistic personality but occasionally starts laughing like a villain if his plan succeeds, even if others are present. Yū can also be perverted at times whenever he possesses a girl's body. He uses his ability to cause fights among people he dislikes and to cheat on tests by possessing smart students and memorizing their answers. He cares little for other people, including his classmates and strangers; he even orchestrates an accident to "save" Yumi Shirayanagi without any concern for the truck driver he possesses. The only exception to this apathy is his younger sister. Although he attempts to form a relationship with Yumi, when he leaves her behind after she fell while he was trying to escape Nao, it becomes clear that he only likes Yumi for her looks.
He also loves to eat good food to the point of crying, the reason being that his sister adds pizza sauce to everything she cooks for him (even french toast). After being forced to transfer to Hoshinoumi by Nao, Yū's personality slowly begins to change for the better. At first, he is clearly against using his ability for anything he doesn't want to and only does so after urging from Nao, though this changes as time passes. Although he dislikes Nao in the beginning, he feels sympathy for her regarding the situation with her brother and her difficult past, as well as her rocky relationship with other students. Throughout the series, Yū acts as a comedic straight man whenever something bizarre or abnormal occurs due to the other members' antics. An example of this is his reaction to Jojiro Takajo's physical state after using his ability to get lunch from the cafeteria, or his reaction to Misa Kurobane's threats to burn things. He unknowingly begins to enjoy his time as a member of the student council, as evidenced at his excitement at winning the baseball match in Moment of Earnest. As of The Sound You Heard Sometime, he becomes a fan of the post-rock band ZHIEND.
After Ayumi's death, Yū goes through severe depression and instability. He goes as far as locking himself in his room for days, doing nothing but eating instant noodles and watching TV. After escaping Hoshinoumi, Yū's mental state continues to deteriorate, and he begins picking fights with gang members, finding joy in having them beat each other up while he possess them and injures them. He is also shown to be borderline sadistic, as he laughs with glee after stabbing one such gangster in the leg with a wooden skewer. He continues to go in a downward spiral and even reaches a point where he is about to use drugs. This goes on until Nao stops him.
After returning to Hoshinoumi, Yū is noticeably more grateful towards his fellow members and is much more accepting of their antics, seeing them as close friends. He begins to try to move on from Ayumi's death but finds himself reminded of her constantly, including a number of times when he thinks about calling home to tell her he'll be late, only to realize she's not there anymore.
His encounter with Sala Shane allows him to realize that he has become more gentle and considerate towards those around him, and that it was Nao who caused him to change over time. This new attitude is shown when he takes Sala to meet Kazuki Tomori in the hopes of curing Kazuki's mental illness, despite there being no gain for Yū. He also begins to develop feelings for Nao, though he never directly says it until later on.
In the original timeline, his personality is the same as it was when he met Sala. Despite the fact that he never met Nao in this timeline, it is also implied that he never developed his villainous tendencies, possibly because of his older brother's good influence on him. He is still a caring older brother to Ayumi, and everyone thinks he has a sister complex. He also cares greatly for and looks up to his older brother, Shunsuke, and has a lot of faith in him, even risking his own life to save Shunsuke so that he could time leap and change the past.
As a child, Yū is shown to be quite responsible for his age, as he helps Ayumi cook breakfast and later scolds Shunsuke for sleeping late instead of making breakfast.
During the events of Charlotte, Yū ultimately overcomes his selfish nature completely; despite his initial fears, he attempts to rescue Nao and Kumagami from a group of foreign terrorists who want to use him for their own goals. Later, Yū is saddened when he learns of Kumagami's death, and he feels responsible for it.
As of Promise, Yū is shown to care for his friends immensely and wants to be able to protect them from harm, no matter how much danger he may have to face. This, as well as his promise to Nao, allows him to decide to take a huge risk and attempt to plunder all abilities outside of Japan. His determination is strong enough to snap Shunsuke out of his depression over Kumagami's death.
Over the course of his journey, Yū's abilities, as well as the constant danger he faces, begin to take their toll on him. He shows signs of PTSD and is unable to sleep, and if he does sleep he sleepwalks and attacks enemy ability users as well as innocent civilians. Gaps in his memory start to form, and he finds himself unable to remember either his past or his goal. He isn't even able to remember Nao, but he is able to remember their promise. He also appears to no longer fear death, either because he could save himself using his newfound abilities, or because he is becoming emotionally numb. As time passes, he embraces the moniker "One-Eyed Grim Reaper"; it is implied that he has forgotten his own name at this point, and he begins plundering abilities with glee. He briefly shows signs of his old, narcissistic, ability-abusing personality but ultimately forgoes this way of thinking when Nao's flashcards bring on feelings of regret, as well as determination to keep his promise, despite his inability to remember who he made this promise to, or why. He continues to plunder abilities in a somewhat emotionless state, though does seem to get angry at enemies occasionally. At the end of his journey, he is a shell of his former self, almost completely devoid of emotion. He barely even shows much, if any reaction having three arrows shot into his back. Despite this, he saves the life of the last ability user and tells her to get to safety after plundering her ability of courage, thereby completing his mission.
At the end of the series, Yū has lost all of his past memories. As a result, his personality is a blank slate. However, he is still similar to how he was before he left, as he tells Nao not to cry, showing he has retained his kindness despite the trials he has faced. Yū now looks forward to making many new, fun memories with his friends as he moves towards the future.
In Happiness You Did Not Notice, when everyone discovers that Ayumi might have a dangerous ability called "Collapse", they go to her middle school but are too late as Ayumi's ability awakens causing the building around her to collapse and she dies.
Yū starts getting frantic about the accident and searches for Ayumi's body. While searching, a piece of the building falls on Yū and he awakens in The End of the Exodus to the shocking news that Ayumi has died. He goes into a state of shock and becomes mentally ill. Due to this, he ignores Yusa, Jojiro, and Yumi when they visit.
He runs away from home to avoid the student council from finding him and picks fights with ruthless people and wins due to his ability. He spends a lot of money on instant noodles and pizza during this time. After assaulting multiple people, Nao appears just before he uses cocaine and reveals that she has been watching him the entire time being invisible to only him. She makes him a dish with one of Yū's mother's recipes which Ayumi used to make. To which he starts crying even though he thinks it is too sweet and disgusting.
Later he promises to rejoin the student council. The day that Nao announced that she had tickets to see ZHIEND, Yusa, Misa and Jojiro had forced Yū to go with her. It was also on that very day that he had coincidentally met with the lead singer, Sala, outside of school. He was then forced into taking her to eat but was shocked to believe he was right, that she was indeed the singer. Her capability in being able to do things whilst blind had kind of fascinated him, especially when she's able to detect his expressions from his breathing.
Yū had politely and kindly taken her many places, one of them was back home so that she could pray to his little sister, who he told her about. He even thought that Nao would want to come meet her but Nao had declined the offer. It is then revealed that, over the phone, he asked Nao if he could take Sala to see her brother just in case a miracle were to happen if she was there. Nao said it was a possibility and allowed them to go so Yū took Sala out to the hospital where Kazuki was "composing" music.
Sala then began singing and after she finished, Yū thanked her because Kazuki had finally become sane. The first thing he even did was to ask if Kazuki remembered his sister. Later that night, Sala went back with a bodyguard for the concert the next day, and Yū went back home. Outside his apartment door, he received a call from Nao, who thanked him for his help. It is also shown that he might have some love interest with Tomori Nao since The Sound You Heard Sometime. In The World that is No Longer Here, it is confirmed that Yū has feelings for Tomori Nao, as he keeps staring her time to time and blushes most of the time he sees her face and is not able to meet eyes to eyes with her correctly. He is even shown to feel uncomfortable when he see's Nao and his brother Shunsuke getting along so well. Especially seeing Nao's change in attitude only towards Shunsuke, not seen towards anyone until this episode.
In Plunder, it is revealed that Yū gained the abilities of those he possessed in the past who had special abilities. He later possesses his brother, Shunsuke, in order to take his time-leap ability to go back to the day before Ayumi dies and save her. After gaining time-leap, he goes back in time and wakes up the morning before the day Ayumi dies. He successfully stops and saves Ayumi from her classmate and then on the way back home they meet Kumagami and Medoki. Yū asks them to take them to meet their brother, Shunsuke.
In Charlotte, a group of foreign terrorists took Kumagami and Nao Tomori as captives to get Shunsuke to bring Yū to them. Shunsuke convinces Yū to go alone to confront them with his ability. But when Yū had arrived, he found that the terrorists have planned out everything very well. While fighting he tries to use time leap but cannot because the attacker had slashed his right eye. Then due to that Yū cannot help but use the collapse ability and succeeds in stopping the terrorist attack, but was not able to control his power thus causing Kumagami to sacrifice himself to protect Nao Tomori.
In Promise, Yū is shown to be on a bed and his body is tied to the bed tightly restricting many movements. When he gets up he remembers what happened while fighting against the foreign terrorists and it activates the Collapse ability which is calmed down after getting injection in his hand from Shichino. Later he finds out that Nao was saved by Kumagami, but he died in the process and he blames himself for it. His brother Shunsuke is also shown depressed and has not moved even a bit and is sitting on a bench at the rooftop of the hospital. Jōjirō comes to visit and brings beef tongue curry with him and feeds it Yū which brings him back to a good mood. Next, Yusa comes to visit Yū and brings cream stew with her and feeds it to Yū which he compliments for being good. He later calls for Misa, and Yusa and Misa switch. He tells Misa that she should visit her parents while she still has time as a Special Ability User because they won't know when Yusa's ability will disappear to which Misa agrees.
Then Yusa goes to visit her parents and switches with Misa. She cries while eating her parents homemade food, knowing it's filled with their love. After some days, Ayumi comes to wish happy birthday to Yū when he turns 16,and feeds him omelet-rice made with the special pizza sauce but it is very tasty, even though convinced that the taste is the same, but knows that it is "filled with love" as Misa had said. Later he goes to try and cheer up his brother and remembers about himself being in almost the same state when he had lost Ayumi in a different timeline. So he fails in cheering his brother up.
When he comes back to his room in the hospital he is surprised seeing Nao in his room. He later asks Nao what to do to save everyone. Nao says he can travel overseas and take everyone's abilities and then let it disappear by taking the vaccine developed by the research center. He takes her advice and says he will do it so he can be the one to save Nao this time. When she asks why, Yū confesses his feelings for Nao saying that he loves her because she was with him when he had fallen into depression and helped him stand up again in his life, however that was in another timeline and thus Nao has no knowledge that it had happened. Confused, Nao does not accept his love confession, instead she makes a promise with Yū that when they meet again someday after he takes everyone's abilities, they will become lovers. She then asks him to start by taking her ability and he does. Yū convinces his brother and friends about Nao's plan. Jōjirō and Yusa meet Yū and tell him to take their powers as well. Later he leaves his house to go overseas after meeting Nao and trading a deck of cards with different languages which Nao personally made it herself with the music player initially received from Nao, which Yū tells her to safe keep till his return.
In Memories to Come, Yū starts his journey to take everyone's abilities, first, he tries to find someone who can search for other ability wielders, he starts off in a city in Philippines. After finding a guy named Angelo and taking away his ability to find other ability wielders, he continues searching. After going to Africa and then Egypt, other ability wielders have started to call him "The One-Eyed Reaper", which he remarks to be an "embarrassing name". In a city in Cuba, Yū is seen lying in bed, screaming at something to "shut up" while hearing multiple voices in his head. His irritation and instability because of this causes his to subconsciously activates Collapse, making everything around him crumble, including his phone which explodes, cancelling the incoming call from his brother. He then stands up from within the rubble, ready to strike at a random person with his telekinesis, however he stops himself just in time telling himself to not kill anyone. It is debated whether or not he was channeling.
In Western Saudi Arabia, he is seen lying in bed again, black eye-rings surround his eyes. He convinces himself to sleep with the help of some pills and falls asleep. He wakes up the next day and finds out that he had eradicated a terrorist force when he was sleeping, stealing the powers from the children the terrorists were using. After traveling from country to country, which included Italy, Portugal, the United Kingdom and many others, he slowly loses his sanity, forgetting the promise he made with Nao, only to be reminded by the deck of language cards made by her. However ,he forgets who Nao is, saying that all he knows is that that person was dear to him. He accepts his name "The One-eyed Reaper" going about stealing other people's abilities in a carefree manner, even saying that he is so powerful that he is god. Finally, in Beijing, where he has one final person's ability to steal, his physical strength now is so weak that he requires a walking stick to stand. He is attacked by a man with a crossbow, who says that he can live a peaceful life after collecting the bounty that was put on Yū's head. Yū is then saved by the ability wielder he was supposed to steal, with the power of courage, he then steals the power and sends the girl home. As he walks away, he is then shot in the back again with a fourth arrow by the man, causing him to fall onto the floor. Yū's brother then comes in a helicopter and and saves him just in time.
Yū wakes up in a hospital bed, with Nao sitting beside his bed. He tells her that he does not recognize her, to the dismay of Nao. She tells him that he is her lover, to which he again says that he doesn't recognize her. She realizes he had kept the deck of cards throughout his journey, he tells her that to him it was a good luck charm, which she starts to tear up at. He then tells her to not cry, which shows that he regained his kindness. He holds her hand and comes to realize that in time he will be able to fully accept her as his lover. They are then in a field, with Ayu, Jōjirō, and Yusa, with his words being "I'm looking forward to what's to come.".
Main article: Plunder
Yū has the ability to take over someone's body for approximately 5 seconds. He initially used this power to posses honors students during their exams to memorize and steal their answers. While in use, his irises become lime green and his pupils become light teal. However, his body slumps into unconsciousness while this ability is in use. Recently, it has also been discovered he can use other abilities whilst controlling their bodies. However, the five seconds time limit still applies. As of The World that is No Longer Here, it is revealed Yū's true ability is "Plunder" which takes someone's ability away from them (They can't ever use their ability again) and use it as his own. Plunder seems to have no limit to the number of abilities it can steal, which proved useful for Yū's plan to plunder every ability in the world.
Plunder, as with all other abilities, has it's faults and limitations. The first is that while Yū is possessing someone, he leaves his own body exposed to danger. This hasn't caused any trouble for Yū though, as he uses his maximum of 5 seconds efficiently by injuring other opponents and then the host before time runs out. While in another person's body, Yū also feels the pain inflicted to the host, though he will sustain no lasting injuries due to him returning to his real body shortly after.
Another drawback is that with each ability Yū plunders, the more he seemingly loses his memories, sense of self, and sanity as a result of the mental strain of possessing multiple abilities. While the effect is minimal and is hardly even noticeable, it is shown that the abilities Yū plundered on his journey across the world built enough of this effect that he was often capable of being seen as mentally unstable, with Nao's deck of cards being the only thing dampening and even reversing this effect to an extent by reminding him of his purpose. By the end of his journey, it is clear that the likely tens of thousands of abilities Yū plundered across the world provided enough of a toll on his mind that his personality was set to that of a blank slate, though he was able to keep the kindness he had before he embarked on his journey. It is also remarked by Nao that it's a miracle Yū is even capable of speech after handling the mental burden of possibly tens of thousands of abilities.
A third limitation is that Yū retains all abilities he plunders and uses retain their drawbacks and limitations for him, such as when his vision slightly worsened as a result of using Time Leap, which was the same drawback that eventually blinded Shunsuke after his countless uses.
- Even with thousands, or likely even tens of thousands of looted abilities at his disposal (Memories to Come), he frequently uses Telekinesis and Barrier as his go-to abilities during battle for offense and defense, respectively.
- He has the same voice actor of Gin from Hotarubi no Mori e, Yuri Plisetsky from Yuri!! on Ice and the same English voice actor as Noctis Lucis Caelum from Final Fantasy XV.
- A running gag occurs whenever Yuu uses his power to take control of someone else, his body slumps forward in a humiliating pose where he's bent over on all fours,with his head face-planted and his rear protruding upward.
|Main Characters||Yū Otosaka • Nao Tomori • Jōjirō Takajō • Yusa Nishimori • Misa Kurobane • Ayumi Otosaka • Shunsuke Otosaka • Takehito Kumagami|
|Supporting Characters||Maedomari • Medoki • Shichino • Furuki • Sala Shane • Kazuki Tomori • Yumi Shirayanagi • Tsutsumiuchi • Konishi • Udō • Arifumi Fukuyama • Saitō • Iori Sekiguchi|
|Minor Characters||Mishima • Kōta • Shō • Nomura • Oikawa • Sugimoto • Takato • Yoshiyuki Ōmura • Gondō • Hosoyamada • Mr. Kurobane • Mrs. Tomori • Honoka|