School Days Wiki
Sekai Saionji
Saionji Sekai.jpg
Age 15
Born December 7, 1990 (Sagittarius ♐️ )
Blood-Type B
Gender Female
Height 155cm (5’1”)
B.W.H 84-62-86
Hair Dark brown
Eyes Dark blue
Affiliation Sakakino School Class 1-3

Radish Restaurant

Occupation High School Student

Radish waitress

Family and Relatives Shun Hazama (father/maternal half-uncle)

Youko Saionji (mother/paternal half-aunt)
Tomaru Sawagoe (double grandfather)
Ms. Sawagoe (great-grandmother [via Tomaru])
Hatsuka Hazama (paternal grandmother)
Moegi Inou (maternal grandmother)
Mrs. Inou (great-grandmother [via Moegi])
Jou Inou (great-grandfather [via Tomaru and Moegi])
Mai Kiyoura (double half-aunt/maternal first cousin [via Kagura])
Miki Sawanaga (maternal cousin [via Ayumu])
Taisuke Sawanaga (maternal cousin [via Ayumu]/potential lover)
Yukari Nagawa (double half-aunt)
Midori Nagawa (maternal cousin [via Ayumu])
Sakura Nagawa (maternal cousin [via Ayumu])
Setsuna Kiyoura (paternal half-sister/maternal cousin-niece)
Hanon Nijou (paternal half-sister)
Kazuha Nijou (paternal half-sister)
Futaba Nijou (paternal half-sister)
Inori Ashikaga (paternal half-sister)
Roka Kitsuregawa (paternal half-sister)
Kagura Inou (maternal aunt/paternal half-aunt)
Ayumu Inou (maternal uncle/paternal half-uncle)
Tomomasa Sawagoe (double half-uncle)
Makoto Itou (double half-uncle/potential lover)
Itaru Itou (double half-aunt)
Children [via Makoto]

Seiyuu Shiho Kawaragi
(credited as "Kaname Yuzuki" in the games)

Sekai Saionji (西園寺 世界 Saionji Sekai) is one of the two main heroines of School Days and appears as a secondary character in Summer/Shiny Days and Cross Days.


Sekai is the only daughter of Youko Saionji and Shun Hazama. Sekai was never told who her father was, with Youko only describing him as a "hopeless good-for-nothing".

She grew up in Motehara along with Setsuna Kiyoura and Niki Ookuma, though she and Setsuna later distanced themselves from Niki.

Sekai was always fighting with Niki and during one of those fights, she met Noboru Matsukata, a middle-schooler who lived above the Saionji's apartment. Her friendship with him was normal at the beginning but escalated quickly into molestation on Noboru's end.

Sekai seemed to love the attention she received since she kept going to "play", especially loving getting patted by Noboru during this "play" as he claimed that she looked really happy with that. Youko never seemed to notice anything.

After enrolling in Sakakino High, Sekai became aware of Makoto Itou after he saved Setsuna from some bullies and decided to research him on Setsuna's behalf, only to develop feelings for him herself.



Sekai has an average build with below-average height with an average bust.

She's described as one of the cuter girls in class by Makoto, and her friend Nanami Kanroji comments that most of the girls would kill Sekai if she said: "I don't feel confident about my body" in her class. She has deep brown hair that reaches slightly past her shoulders and curls slightly from behind, as well as one "idiot hair" curling upward. She's often seen in her school uniform and white sneakers, but her casual clothes usually consist of a white spaghetti strap shirt with a pink jacket and a dark blue miniskirt. Later, she buys a pink coat she has had her eye on for a while after she saves up enough money. If she's depressed, Makoto expresses concern for her, saying that she's gotten skinnier and sickly-looking.

Before going to the pool, she can go shopping for a swimsuit with Nanami and complain about how swimsuits go out of style every year. She can also be seen in a different swimsuit almost a year later on the alternate ending.


An emotional side few know

Sekai is an outwardly cheerful girl who cares deeply for her friends and seemingly helps Makoto out with Kotonoha only for fun. She often berates Makoto every time he does something inappropriate to a girl. But it's revealed she's very emotional and can spend days crying in her room. She is also unwilling to reveal to Kotonoha Katsura that she and Makoto are dating. But when she sees Kotonoha alone at a reception desk, she feels guilty, having taken Makoto away from her. Above all, she has loved Makoto for a long time and can go into depression when he starts dating Kotonoha, something that can worsen if Setsuna leaves for Paris.

The Visual Novel

Her VN version is the most caring of all her adaptations. She's capable of distancing herself from Makoto and Kotonoha and only gets together with him if he pursues her. She's very afraid of losing Makoto and can be devastated if Setsuna goes to Paris. Oddly enough, despite Kotonoha's potential to go insane from a bad breakup, Sekai is shown to be somewhat more incapable of letting go of Makoto than Kotonoha is in some routes. It is best evidenced by how, should she end up dating Taisuke Sawanaga, she will always break up with him due to still loving Makoto, whereas Kotonoha will remain with Taisuke unless Makoto proactively tries to win her back.

She also believes in the cellphone charm and is seen doing it with Makoto; if it works out for her, she can tell her friend Hikari Kuroda that the charm does indeed work. She's also mentioned to have sharp perception by Makoto. She is, to a slight extent, worldly wise, as demonstrated by her ability to give valuable advice to both Makoto and Kotonoha when their relationship gets rocky. However, this insight fails her when she is involved.

At the height of her depression (Makoto dating Kotonoha, Setsuna going to Paris, and her dating Taisuke, a guy she doesn't even like, or in Summer/Shiny Days, Makoto dating Setsuna), she mentions to Kotonoha that she wants a dad. This appears to be the core of her emotional instability during the events of Summer/Shiny Days, as Sekai subtly shows jealousy toward Setsuna, who still has her father nearby, unlike her (though ironically, Sekai's father is also Setsuna's).

Sekai genuinely doesn't want anyone to get hurt because of her. Though unwilling to go through with it, she pressures Makoto into telling Kotonoha of their relationship, or, despite her crush on Makoto, decides not to get involved in his and Kotonoha's relationship. She is genuinely shocked and apologetic that her friends have been bullying Kotonoha behind her back, to say nothing of Nanami's urging they do so for her sake. Her only instances of physically harming other people involve her going into Yandere mode upon her getting pregnant and subsequently subjected to both depression and abandonment.

Sekai accepting Kotonoha's kiss.

If dragged into a three-way relationship, Sekai is initially resistant and doubtful, not entirely convinced about the rightness of such a relationship.


In the anime, she's more selfish than her visual novel counterpart; for example, she had an ulterior motive to get together with Makoto anyway, ignoring Kotonoha, while in the VN, she only does so if Makoto genuinely proclaims his love. She also concerned less with the wellbeing of others, such as Kotonoha being cheated on, and furthermore doesn't break things off when Makoto starts to cheat on her. However, she does attempt to stop the affair early on after she realizes the damage she has done and tells Makoto to leave her alone and stay loyal to Kotonoha. However, Makoto convinces Sekai that he loves her more and implies that he broke things off with Kotonoha.


Her manga version is mostly the same as in the anime, the difference being that she accepts Makoto loving Kotonoha more and even accepts Makoto dumping her. However, she goes insane after Makoto is critically wounded protecting her from a yandere Kotonoha.

School Days

In all versions, Sekai initiates all the events by setting up protagonist Makoto with Kotonoha and indirectly causes all the good or bad events to happen.

When not on the rooftop with Makoto and Kotonoha, she usually eats lunch with Setsuna, Hikari, and Nanami during school, but after she starts having lunch with Makoto, they can get the wrong idea about her and Makoto.

Visual Novel

She decides to do some research on Makoto for Setsuna but falls in love with him herself. She has no idea how to approach him, and he pays attention to nothing, let alone her. A surprise seating rearrangement occurs, and Sekai is assigned next to Tanaka. She then learns that Setsuna has been assigned next to Makoto and begs to switch with her, to which Setsuna agrees.

She tries to get to know Makoto, but immediately learns of his crush on Kotonoha and decides to help him make Kotonoha his girlfriend. Presumably, because it's her only excuse to stay close to him but also because she wishes to see him happy - and possibly, if not depressively, figuring he'll never have eyes for her. Together they have lunch every day to learn about Kotonoha, and she inevitably succeeds in putting them together. Before Makoto goes on his first date with Kotonoha, though, Sekai kisses him and claims it's only a reward for her hard work, although she is shown distraught over succeeding. From then on, depending on how the story goes, she can end up with Makoto, end up depressed, get killed, or go insane and kill Kotonoha or Makoto. See this for more details.


Sekai's role is mostly the same; however, the series focuses more on Makoto's affair with Sekai, and the other girls in the series. Sekai is a good friend of Makoto at the start of the series and wants to help him get involved with Kotonoha. However, she develops feelings for him and uses Kotonoha's hesitance to allow Makoto to practice anything using her body, claiming it not to mean anything to her. While she does feel guilty for getting involved with Makoto, even to the point of trying to ignore him for Kotonoha's sake, Makoto manages to convince Sekai that he loves her and not Kotonoha.

As the series progresses, she discovers that Makoto is sleeping around with other girls and, still reeling from Setsuna's sudden departure to France, does nothing about it until she discovers that she could be pregnant. However, he refuses to take responsibility, and the other girls stop taking an interest in him, causing their relationship to worsen. She is slowly driven over the edge as Makoto rekindles his relationship with Kotonoha.


Sekai's role is almost the same as in the anime. The major difference is that she is far more forward about her feelings for Makoto but ultimately accepts him loving Kotonoha more than her. She even shows a willingness to remain friends with Makoto and accepts being dumped with a smile.

However, towards the end of the manga, Kotonoha goes insane and accidentally stabs Makoto in an attempt to murder Sekai. Makoto survives and is rushed to the hospital, but in the meantime, Sekai passes into Yandere territory and kills Kotonoha a week later. When Makoto knows Kotonoha was dead, Sekai mock at her and claims it was justified because she was insane and dangerous. She then goes on to say that from now on, she'll be the one who brings Makoto happiness, and she wants to start over with a clean slate.

Summer Days / Shiny Days

Sekai's role is smaller in Summer Days/Shiny Days due to her being sick with the mumps. Due to this, she asks Setsuna to fill in her place as a waitress at Radish, where she works by bargaining with her that she might meet Makoto as he lives nearby. Some of her friends besides Setsuna, such as Niki and Ai Yamagata, also visit her during this time. Still, Sekai's laziness gets to her, and she begins to continue feigning sickness to relax and snoops around at Sakakino Hills, the latter catches up with Setsuna.

Many of Sekai's hidden insecurities and jealousy surfaces, when Setsuna reveals to her (and Ai) that Makoto is her boyfriend at Radish. As Sekai also loved Makoto, this significantly depressed her, but she still tries to be calm and wants Setsuna to be happy. However, when Setsuna runs away to Paris because of her not properly telling Makoto that Shun is her father, Sekai's suppressed emotions all come out, causing her to tell Setsuna that she loves Makoto more than her.

Sekai forced into pregnacy by Youko and Mai

In the semi-canonical Paris for Four ending, Sekai learns that both Kiyouras and even her own mother Youko are all pregnant with Makoto's children. After she accidentally blurts that she feels left out, she is then forced by everyone to join their pregnancy party, which is implied to quickly happen as Makoto is right outside the door.

Cross Days

Sekai getting buried by Yuuki

The Visual Novel

Sekai's role is rather small and reduced, but for most storylines, she has involvement with Makoto

Depending on which route you take, Yuuki Ashikaga will try to end the affair between Sekai and Makoto but cannot convince either of them. In one route, Yuuki might not only attempt to kill Sekai to stop the affair, but he also may attempt to molest or blackmail her, only for Setsuna to rescue Sekai.


Yuuki tries to convince Sekai to stop stealing Makoto away from Kotonoha, but is told that it's none of his business. In the end, it's revealed that Sekai and Kotonoha are both in a three-way relationship with Makoto.


  • Her given name Sekai [世界] means "world".
  • Her surname and birthday originate from Kinmochi Saionji [西園寺 公望], a statesman and three-time Prime Minister of Japan.



Main article: Sekai Saionji/endings


  • Sekai's appearance is similar to that of Nagisa Furukawa from Clannad and Kagome Higurashi from Inuyasha.
    • The commonality goes even further with the case of the former: Nagisa marries Tomoya Okazaki (who resembles Makoto) and has a daughter with him.
  • Sekai has five endings, which is less than Kotonoha's. But unlike Kotonoha's, all of them are unique.
    • If one counts Setsuna's Feelings to be a Setsuna ending, even though Makoto ends up with Sekai, then all of her endings are shown ending with a hug.
  • In the anime, Kotonoha says that Sekai was lying about her pregnancy due to her seeing nothing in Sekai's corpse. She could be wrong because an embryo would not have had enough time to develop long enough to be seen until weeks after being conceived.
    • It is also possible that she mentally believed herself to be pregnant from all of the stress she suffered up until that point since after 3 months of pregnancy, the embryo would be noticeable.
  • Sekai used to heavily believe in the phone wallpaper rumor and if she ends up with Makoto, she can assure that it works to Hikari.
  • According to the official family tree, Makoto has children with Sekai and Setsuna though the official continuity is still unknown; see this.
  • It's likely that she inherited her blue eyes from her paternal grandmother.