|Voice Actress||Shiho Kawaragi|
Sekai is a lively classmate of Makoto Itou who one day discovered his crush on Kotonoha Katsura after being seated next to him. To make up for this she offered to help him get to know her, but there seems to be more to the motive than she lets on...
Sekai has a light complexion and is average height but with a small bust. Her eyes are midnight blue and she has brunette hair nearly chest length with similar shaped bangs and a long, thin cowlick. Late in the series, it is noted that she has began to look thin and sickly.
Normally Sekai is depicted in the school uniform, and she is shown having a plain and basic, slightly feminine casual attire. During winter she wears an expensive winter jacket she saved up money to afford.
Sekai is a typical teenage girl with normal teenage situations- like school, friends, having a part-time job, and romance. Usually she is cheerful and lively, and she is shown to be kind to others but she can also be nosy and pushy when she attempts to help others. She is playful and enjoy teasing others, and her approachable nature makes her very close to her friends. She is also very passionate, bold, and stubborn and quick to chastise someone for being an idiot if they do something to cause trouble or make a very obvious mistake. However, in a relationship she is shown to become submissive.
One of Sekai's biggest concerns is that she is highly emotional, and she can become bitter and aggressive towards those she puts blame on for making her upset. Her moral stability is also brought into question due to her impulsiveness. While she wants others to be happy, she struggles with trying to ignore her wants and desires, and is shown having a lack of guilt for her poor decisions later on. She is shown forgetting logic and is unable to consider the consequences of her actions, and she can be cowardly.
Deep down, Sekai is revealed to revealed to suffer from feelings of inferiority and depression. She seeks the attention of those she cares about, and if ignored or left alone she struggles to function. She needs to be needed by those she cares for, even when knowing she might have to distance herself from them.
There are several facets of her personality that differ between media:
In the visual novel Sekai is selfless and friendly, and despite her feelings for Makoto she insists on keeping distance if he shows interest in her. But if he keeps trying to pursue her she eventually gives up resistence, although she feels guilt for most part. She was distraught finding out her friends are some of Kotonoha's bullies.
In the Anime, Sekai remains friendly but her selfish and impulsive traits are played up more. It is implied from the start that she has ulterior motives, and once she hooked up with Makoto behind her back she began ignoring Kotonoha. Initially she did tell Makoto off after seeing how much damage they were causing, but she resumes the relationship with no guilt after he claims they broke up.
Her manga portrayel is shown to be the worst, actively pursuing Makoto from the beginning and using any chance she could to bond with him until he gave in and agreed to break up with Kotonoha to be with her. She was shown to be indifferent and cold.
In one of the spin-offs she is shown to be on much better terms with everyone.
Sekai had a mostly average childhood other than her father abandoning her and her mother. She knew Makoto through Setsuna, who she offered to help gain his affection. But in the process she ended up developing her own feelings for him and apologetically explained this to Setsuna. Setsuna agreed to let her have a chance with him and made it her goal to help Seika win Makoto over.
Unlike Kotonoha, who attacks others for the pain caused to her, Sekai focuses on Makoto unless pushed far enough to target Kotonoha.
For a full list visit Sekai's Relationships
Parents - Sekai lives alone with her mother and they have a close relationship, usually confiding everything in her. She has learned a lot from her mom. She despises her lecherous father for abandoning them.
Makoto - With as much time invested in getting to know him on two occasions, Sekai fell for the kind guy she thought he was. Initially she had to force him to make a move after offering herself up to him for practice in winning over Kotonoha, but her various responses to him pursuing her change depending on the media. Around him she is a Tsundere, unable to honestly speak about how she feels until their bond strengthens, and she has no problem chewing him out or yelling at him when he ticks her off or does something stupid. Makoto thought she was really annoying initially, but he found himself using her to fulfill his sexual needs because of how withdrawn Kotonoha was; but depending on the route or story he grows to genuinely like her.
Kotonoha - She is very envious because of Kotonoha's popularity with boys, wealth, and developed body, but she holds no ill intentions towards her. She genuinely gets along with her -either out of kindness or because she faked it- and was happy to hear she hooked up with Makoto. But once he begins wavering between them she struggles to try to cover it up. She doesn't seem to want to hurt Kotonoha and was startled when she begins expressing her violent tendencies, and should Kotonoha lash out at her or if she feels threatened their friendship is ended. However, in the threesome route ending and in the spin-off manga, Sekai is surprisingly shown to become the hesitant and withdrawn one in the group.
Sekai was killed in the anime finale, and she can suffer multiple deaths in the first game.
- Bloody Conclusion - The most common death for Sekai and the most infamous for the series. As she, Makoto, and her friends walk across a bridge they are approached by the mentally broken Kotonoha. She attempts to kindly greet her, unaware of danger and is unable to react in time to avoid having her throat slit by the weapon Kotonoha was holding. Sekai bleeds out violently and falls over as everyone reacts in fright.
- Innocent Evening Sun - Sekai pushes Kotonoha down on the train tracks but is pulled down with her. The girls get into a fight unaware of the approaching train and are unable to react before it hits them.
- Twisted Hair - Like above, but Kotonoha survives. As Sekai tries to escape the tracks her phone falls from her pocket and she tries to reach or it, allowing Kotonoha to use her body as leverage. Makoto assists her in getting out, just as Sekai grabs her phone and the train collides with her.
After Makoto and Kotonoha began reconciling Sekai discovers she is pregnant. She attempts to make him take responsibility but they try to convince her to have an abortion instead, suggesting they know a good doctor she could have the procedure done by. She refuses and began to harass the couple until the stress caused her to become sickly and depression set in. She makes a final, desperate plea for him to do the right thing after they return from a date but after she angrily assaults Kotonoha she is thrown out after Makoto tells her off. Seeing them makeout in front of her causes her to give up on him. Still hurt and feeling betrayed, Sekai approaches Makoto at school and asks or him to meet up with her to speak. They agree to hold conversation at his place and later they reunite, where things are shown to begin normal and they appear to be fine. But once he brings up abortion again they resume arguing, but he calms down and offers to get her a drink. She agrees, but asks to get it herself and leaves for the kitchen. She grabs one of the knives and sends him a text message, which he responds to with confusion not understanding it; and just then she attacks, stabbing him in a blind rage over the course of a few minutes. She snaps out of it to see what she has done and she runs away. Hourse pass and Sekai has taken shelter in her bedroom, when she suddenly receives a text from Makoto asking to meet up. Knowing very well it isn't him she brings the knife up to the building's roof, where they agreed to meet and she finds Kotonoha with a bag. She reveals what happened and shows Seika the bag to reveal she decapitated Makoto, causing Seika to become physically ill in response. Realizing Kotonoha got her there to kill her, she attempts to strike her first but she isn't capable of reacting quick enough and Kotonoha slices through her, leaving her fatally wounded and to bleed out. Before leaving she slices in her further to see if she was pregnant like she claimed.
"Makoto-kun, Help Me!" - mockinginly quoting Kotonoha in the Manga when telling Makoto about killing her.
- Due to her behavior and greed, most fans see karma getting back at her in the spin-off games. While Kotonoha remained a main love interest, Sekai ended up becoming a side character with a lack of involvement and endings, inlcluding one game that wrote her out for a good part of it by saying she was sick. Her routes and endings were given to her Mother and other possible Love Interests.
- Sekai vaguely resembles Kagome from Inuyasha.
- It is never officially revealed if she was actually pregnant, or if it was her own damaged mental state making her believe she was.
- While Kotonoha sees no proof of it in the Anime, it has been pointed out that it was too early for any physical proof, or that she was just in heavy denial.
- Her voice actress provided voice samples for one of the types of Yandere personalities in Artificial Academy.
- It has been noted that Sekai slightly resembles Makoto. With the complicated family charts between the game series made by the company, they are revealed to be non-blood related siblings or cousins through her father.
- Sekai's attack on Makoto and her death scene were altered in the airing of the final anime episode due to concerns it was too graphic. The blood was blood and the gorey detail was lessened, but for DVD release the blood was returned to red and the detail was increased.