Kasuka Heiwajima

"People say that I don't understand others, and they say they don't understand what I'm thinking. I agree. I don't understand myself. But I do know some things. Like a man who watches a girl asking for help and doesn't try to stop her tears is the worst."

- Kasuka Heiwajima, Durarara!!x4

Kasuka Heiwajima (平和島幽, Heiwajima Kasuka) is the younger brother of Shizuo Heiwajima. He is a famous actor, and his fans know him by his alias Yuuhei Hanejima.

Appearance
Kasuka is a handsome young man with long neck-length black hair and features similar to his older brother. He always wears a blank expression, with lidded eyes, always showing little to no emotion, He usually dresses smart casual, his attire consists of a white long-sleeved shirt with a black tie, and he has worn a black dress shirt, with jeans and simple sneakers, and a silver chain necklace.

Personality
As an actor, he is known for his extraordinary skills and was praised as "unbelievable" when he first started. Ironically, when he is not acting, he is a quiet, reserved man who seems to be devoid of emotion and rarely talks unless necessary. According to him, his reserved nature is a result of growing up alongside Shizuo, who is known to be a man of little restraint.

Background
As a child, he was the first to witness his brother's strength as Shizuo picked up a fridge, enraged because Kasuka ate his pudding. Although he shows little emotion, he seems to care genuinely for his brother, despite Shizuo's destructive rage. One or two years after Shizuo graduated high school, he was the one who was initially approached by a talent scout, not Kasuka. As a result, the talent scout would have been beaten to death had Kasuka not intervened. In turn, the talent scout turned Kasuka into a model for magazines. However, he became a famous actor as an adult and has had to spend much time away from Shizuo. Since Shizuo had much trouble holding down a job thanks to his destructive tendencies, Kasuka gave him his trademark bartender suit, hoping to help him find a permanent job and settle down. Unfortunately, Shizuo was framed by Izaya Orihara for a crime he did not commit, and much to his disappointment, lost the job his brother wanted him to keep.

While they do not talk as often anymore, they still both genuinely care for each other. When Kasuka came to Ikebukuro to film a TV show, Shizuo watched him from the back of the crowd because of an online post from someone claiming that he would kill Kasuka because his ex-girlfriend was a huge fan. The man approached Kasuka and was about to stab him when a signboard flew out of nowhere and knocked the man out. Kasuka was the only one who looked to see where the signboard had come from and saw his brother quickly slipping away before he was noticed. It was later revealed that Izaya had been the one who told the man where Kasuka would be, as well as the one who informed Shizuo about the attempt on Kasuka's life.

Kasuka is very popular and has a lot of fans, including Izaya's sisters Mairu and Kururi. Mairu states she would even push Izaya in front of a truck for a chance to meet him. Kasuka also seems to know Shinra because of his brother.

Hollywood Arc
Kasuka returns to Ikebukuro to begin the shooting of his next movie. After a brief dinner with his manager and an interview, Kasuka drives back to his apartment and thinks about visiting his brother before things get busy. Seconds later, he sees the serial killer Hollywood (dressed in a zombie costume) fall out of the sky in front of him out of nowhere. He examines the injured body of the aforementioned serial killer and peels off the zombie mask to reveal none other than the rising actress/singer Ruri Hijiribe.

Kasuka takes the injured superstar to his apartment and calls Shinra Kishitani to treat her wounds. Much to their surprise, Ruri's injuries heal at an astonishing rate (second only to Celty and Shizuo, as Shinra puts it), and she wakes up after a couple of hours. When Shinra is called away for another medical case, she asks Kasuka why he did not just call an ambulance or the police. He replies that, given Ruri's circumstances, he figured it would be better for her if he did not get the authorities involved. Upon hearing his reply, Ruri compliments Kasuka's ability to think ahead and then proceeds to slam Kasuka down on the bed she was in and holds him by the throat, asking whether or not his getting killed was a possibility he had considered.

Kasuka questions her motives for wanting to kill him, saying that if it were to keep him quiet, then the security cameras littered throughout the building would quickly snuff out that plan. Ruri then asks what Kasuka would say if her motives were only to kill him and nothing more. With his usually expressionless face, he replies that he does not wish to die and that he still has loose ends to tie up. Ruri asks what those loose ends are and is visibly surprised by his response.

Aside from not finishing his next movie, Kasuka states that his biggest regret would be keeping Ruri from crying, quoting a line from his role as Carmilla Saizou. He also states that part of the reason he took up acting was to be able to express himself as freely as everyone else, having been deprived of those opportunities thanks to his overemotional older brother. Ruri breaks down after hearing this, realizing that Kasuka is the exact opposite of her. Kasuka was something abnormal, a "monster" of sorts, who wished to become human through finding and expressing human feelings, while Ruri was a human who wished to become a monster. She thanks Kasuka after she regains her composure.

Kasuka, in turn, apologizes to Ruri for having taken extra precautions without her consent. When he had first picked her up, Kasuka noticed several individuals tailing them as they went to his apartment. In order to keep them away, Kasuka lured several reporters to his apartment to provide ample cover for him and Ruri to escape without their pursuers noticing them.

After the manager at Ruri's talent agency, Jinnai Yodogiri goes missing, Ruri switches over to Kasuka's agency, and the two of them become a couple. Ruri decides to tell Kasuka about why she became Hollywood and about her past, but Kasuka denies her, saying that he knew Ruri planned to kill herself once she told him everything about her. With that in mind, he states that he will not hear her out because he does not want her to die.

Adabashi Arc
Kasuka and Ruri go to Shizuo for help regarding Ruri's stalker. Shizuo initially thinks that Kasuka is asking for his blessing for Ruri and him to get married, but instead, Kasuka asks Shizuo to take care of his cat while he works on sorting out the situation.

Kadota's Coma Arc
Kasuka and Shizuo are arrested under false charges (for Kasuka, it was possession of illegal drugs) by a corrupt cop named Kujira. One of Kinnosuke Kuzuhara's subordinates brings him the faulty evidence which angers Kuzuhara greatly. Kuzuhara manages to break Shizuo out of jail, but they are unable to reach Kasuka who is held in a different precinct. As of the end of the arc, he is still held in jail.

Trivia

 * Kasuka has a long-range of hobbies: sports, fishing, billiard, darts, horse riding, investments, collecting automobiles, going to the theater, going to the movies, painting, calligraphy, home carpentry, table magic, aikido, flying small planes, flower arrangement, etc.
 * He loves cats, and owns one that is named Yuigadokusonmaru. In the game, when Shizuo sent a picture of a tiger that he defeated to Kasuka as a sign of thanks for the hot cakes he sent, the latter soon recognized it as an endangered species. His birthday is also known as 'Cat's Day'.
 * He dislikes judging people based on rumors.
 * His favorite foods are homemade curry, rice pudding, and dairy products.
 * He dislikes chewing gum, as he doesn't know how long he should chew it before throwing it away.
 * He also bears a resemblance to Charon Walken, an American child stuntman in Baccano!, set in the same universe as Durarara!!