Tenma Siblings

Tenma Siblings is the family ship between Tsukasa Tenma, Touya Aoyagi and Saki Tenma from the Project SEKAI fandom.

Canon
Touya and Tsukasa attend Kamiyama High (Kamikou), whilst Saki attends Miyamasuzaka Girls' Academy. Touya and Saki are first years, while Tsukasa is a second year.

In their early childhood, Touya had met Tsukasa and Saki through their parents' acquaintance, those two becoming the first two people Toya respects. Though Tsukasa is infamous at Kamikou, Touya doesn't seem to mind. Akito was surprised when Touya mentioned Tsukasa as, "the upperclassmen who I respect".

Saki and Touya often played the piano together, but then drifted apart after Saki had been hospitalized in middle school.

Tsukasa helped give Touya courage to quit classical music and go against his father's wishes, saying that it was okay do to what he wanted to do, despite others' disapproval. Because of his actions, Touya considers Tsukasa as his "savior".

Doll Festival at the Tenma's
In chapter 1, we are introduced to Tsukasa and Saki preparing for Saki's first Hinamatsuri (Doll Festival) ever since she had gotten sick, when Tsukasa notices how worn down the dolls are. This causes him to remember how he had accidentally got them dirty whilst trying to bring it for Saki to see. He then heads to the mall, planning on getting new dolls for Saki.

In chapter 3, Touya notices Tsukasa after buying a book from a bookstore. Touya asks if he's shopping, to which Tsukasa says yes. Tsukasa explains that he's shopping to prepare for Saki's first doll festival party ever since she became healthy. After Tsukasa had said he needed to make this the best party ever, he says, "As expected from you", and offers to help with anything.

After heading to the mall, Tsukasa heads towards a doll store, proclaiming its what they needed. Touya, shocked responds by saying he thought he was just buying party supplies. Tsukasa answers that the dolls were in bad shape, which causes Touya to ask about it. He explains that when they were kids, he had accidentally dropped them when bringing them to young Saki, since she had said she wanted to see the dolls. Touya is more determined to help out.

In chapter 4, they finally arrive home, but come across Saki's friends. After they introduce themselves to Tsukasa, they separate, Tsukasa and Saki thanking Touya for his help.

Tsukasa switches out the old dolls for the new dolls when Saki had fallen asleep, only to be caught red-handed since she couldn't sleep. He confidently says that he bought new dolls, thinking that Saki would be happy, in which she isn't. She proclaims, saying how it has to be her own dolls for her doll festival. Tsukasa tries to argue back, saying how they were worn down, but Saki reminds him of what he did that day it got worn down. She calls him a "big, dumb forgetter".

He says that people would've made fun of her having the worn down dolls, in which Saki responds by saying that her friends, her childhood friends wouldn't do that. Saki says that they're down talking until Tsukasa remembers, and he leaves in a fit of rage, saying to himself, "whats gotten into her?"

In chapter 5, After heading to school, Saki's red eyes are pointed out by her friend, Honami. Saki complains to Honami that Tsukasa had forgotten, and when Honami suggested sending a text, Saki says that he didn't respond, even when he left behind his lunch, leading her to think that she'd spend her first Hinamatsuri badly. Saki believes that Tsukasa was angry at her.

Touya had gotten concerned since Tsukasa hadn't been answering his texts, asking if Saki liked the dolls, only to run into him at school. When he questions him about the texts, Tsukasa finds out he hadn't brought his phone, which answers his question. Touya finally asks if she liked the dolls, in which Tsukasa gives a sad expression, saying that he got into a fight with Saki, because she insisted on keeping the dolls, and blamed him for not remembering what he did that day. Tsukasa apologizes to Touya, before leaving for class.

In chapter 6, Tsukasa refuses to go home after his and Saki's argument, going to the SEKAI instead. But, his argument leaves a toll on him whilst helping out with the Hinamatsuri, explaining his trouble to the VIRTUAL SINGERS. After talking with Luka, Tsukasa comes across Nene, who says that Honami is waiting for him at the school gate. In a panic, he apologizes to Luka for not being able to help out more, before leaving and meeting Honami at the school gate.

He questions Honami if Saki is alright (very loudly), in which she replies that she is. Honami says to Tsukasa that Saki looked down after their fight, and tells him that Saki isn't really mad at him, and blames herself for saying cruel things to him. Tsukasa, after hearing this, rushes back home in an attempt to make it up to her.

In chapter 7, Ichika and Shiho are at the Tenma household with Saki, making some final minute preparations before Honami arrives, in which Shiho comments on how scuffed the dolls on the doll stand look. Saki retells the story of what Tsukasa did to bring it to her and why its so scuffed, in which the two find it heartwarming.

After hearing a knock on the door, Saki rushes to the door thinking its Honami, but it turns out to be Touya. She invites him thinking he came for the party, but he denies it, saying that he needs to tell her something. He explains how they fought, and how it might've been a misconception of each others feelings, but Touya recalls how earnest Tsukasa was when picking out the dolls, and how he saved up money for years and years just to buy the dolls Saki would like. At this news, Saki is down.

In chapter 8, Tsukasa comes running down back home, yelling Saki's name. He immediately apologizes back, in which Saki also apologizes. Both of them are surprised that they aren't mad at each other. Tsukasa blames himself claiming that hes the one in the wrong, and that what Honami told him that she was feeling down all day. He also apologizes for not answering the texts, since he left his phone at home.

Fanon
Tenma Siblings are one of the most popular family ships in the fandom, seeing how Tsukasa views Touya as a brother. Though they aren't blood-related, there is a certain set of people in the fandom who headcanon Touya being actually part of the Tenma family and hence, consider it incest to ship him with either of the Tenma siblings, even to the point of lashing out at people who do so. Some people have also headcanonned Touya actually getting adopted into the Tenma family.

There's a decent amount of fan art of the trio, with some of the fanworks portraying their childhood memories. For those who ship the three in a poly ship, the ship is normally shipped as a solution to decide between TouKasa and Tousaki. Tsukasaki isn't normally shipped romantically due to the two being siblings. Most media often depict fanarts and fanfics of these three, either them bonding together or Tsukasa helping Touya escape from his father.

Mainly on Tiktok, people have often added Kanade into the Tenma Siblings, and in some rarer cases Haruka as well.

Fandom
FAN FICTION

TWITTER

Trivia

 * Their ship is referred to with the "🌟🎹☕" emojis.
 * All three of them have their birthdays in May. Tsukasa, Toya, and Saki's birthdays are all 8 days away, linking in with Tsukasa and the number 88.
 * Touya often gifts Saki the plushies he gets from the arcade through Tsukasa.
 * Tsukasa and Saki are some of the only people Touya calls by their first name (although with honorifics, as he calls Saki, "Saki-san" and Tsukasa, "Tsukasa-senpai").