RyuuSou

RyuuSou is the slash ship between Ryunosuke Tsunashi and Sogo Osaka from the IDOLiSH7 fandom.

Before Meeting
Before becoming an idol, Sogo was a great fan of TRIGGER, thus he knew Ryunosuke and, as the rest of the group, liked him a lot.

Since he was and still is a fan of TRIGGER, Sogo showed great admiration and respect for Ryunosuke as it is shown in part 2, when the two have to work together. Each time he heard TRIGGER on TV, he rushed toward it to listen.

Part 1
In the first part of the game (or first season for the anime), Sogo and Ryunosuke never interact together, Sogo tells Riku that he admires TRIGGER a lot but never talk specifically about Ryunosuke.

IDOLiSH7 Vibrato
In IDOLiSH7 Vibrato, episode 2, Sogo along with the rest of IDOLiSH7 is invited to TRIGGER's creation 2nd anniversary. When Ryunosuke tell that everyone can peak whatever they want to drink, Sogo blushes, stiffs and thanks him while stuttering.

In the 3rd episode, Sogo and Mitsuki go shopping in order to buy TRIGGER goodies. While Mitsuki tells Sogo that he intends to buy Gaku goodies, Sogo hesitates between Tenn and Ryunosuke's.

In the 6th episode, Sogo watches with Yamato a commercial involving Ryunosuke drinking a beer can half-naked. Yamato comments that it was suggestive for a middle-day advertisement while Sogo says that it will "probably sell out again". Later in the same episode, TRIGGER joins IDOLiSH7's party. Sogo, already drunk, welcome them loudly. Later, Sogo poses besides Ryunosuke, both holding their beer can (the same type of beer as in the advertisement).

In the 8th episode, when TRIGGER arrives behind the stage where IDOLiSH7 is to represent, Sogo gets up quickly and stands stiff.

Part 2
In part 2 (or season 2), for Re:Vale's 5th anniversary, Takanashi and Yaotome Productions form 3 units mixing IDOLiSH7 and TRIGGER's members. Sogo and Ryunosuke, along with Tamaki are part of the last unit and train to perform LOVE&GAME's choregraphy. The theme of the song revolves around casino games and romance. During the training, Sogo praise Ryunosuke's dancing skills which annoys Tamaki, who wants his partner's attention. Later, after Tamaki calls Ryunosuke an "ero-ero beast", he reveals that this nickname and the whole sexy, tempter personnality is made up by his agency which surprises Sogo. He also reveals that he is better at making bed rather than "playing" in one and he tells that he has 3 little brother and that his father is a modest fisherman, which also surprises Sogo. Later, the two of them, along with Tamaki eat their bentos together.

Later in the game/anime, Sogo, Ryunosuke and Tamaki continue training for the concert. While Sogo praises Ryunosuke's dancing skills, once again, Tamaki finds accidentally his long lost little sister's charm in Sogo's bag, which upset him a lot. As Tamaki confronts his partner, Ryunosuke separes the two, defending Sogo from Tamaki and tells Sogo to get out of the room as he has a little chat with Tamaki. Ryunosuke manages to calm Tamaki down as Sogo tells the problem to the other members of IDOLiSH7. Later, Sogo gives a message to call Aya (Tamaki's little sister) out to the producer of a show in which TRIGGER participate, pretending that the message comes from the FSC. The message is read aloud by Ryunosuke. When Sogo tells Ryunosuke that he was the one that gave him the message, revealing that he is the FSC president's son, Ryunosuke thanks him for everything his father's company has done for TRIGGER. Sogo feeling embarrassed tells Ryunosuke that he was disinherited by his father having no more link with him. When Tamaki rushes to find Aya, Sogo and Ryunosuke rushes behind him together.

Part 3
In part 3 (or season 3), Ryunosuke approaches Sogo. He tells him that family is really important and he must make up with his father. Sogo thanks him for worrying but tells him that he doesn't want to get involve with family business anymore.

Substories
During IDOLiSH7's 1st anniversary event, Sogo gets drunk. He becomes clingy toward Ryuunosuke and install himself between his legs, using his co-worker as an armchair. Even though Ryunosuke finds this clingy side of Sogo cute, it hurts him to spread his legs at this point. Later, Sogo, still drunk, order TRIGGER to sing and dance for him, except Ryunosuke who just has to sing because he still is his "armchair".

Rabbit Chats
While Sogo and Ryunosuke doesn't interact a lot during the main game, a lot of scattered interaction can be found throughout the rabbit chat.

LOVE&GAME
In the LOVE&GAME Rabbit chat, Sogo and Tamaki stay over Ryunosuke's house. On one hand, Sogo tells that he enjoyed the stay a lot and that Ryunosuke was really kind even though he expected more, being extremely excited to visit his idol. The three of them went shopping, made dinner and played games. Sogo describes Ryunosuke as the model exemple of a man due to his extreme kindness and the pleasant vibe he gives off. On the other hand, Ryunosuke tells that Sogo couldn't drink his hot milk in one gulp and had to drink it sip by sip. Finally, Tamaki tells that Ryunosuke excused himself for the untidiness of his flat while Sogo was kneeling on the floor, loving being at Ryunosuke's. Tamaki also tells that Sogo cleaned Ryunosuke's flat by his own will and asked him to help out. Tamaki also tells that he didn't prepare dinner, Sogo and Ryunosuke both prepared it together.

Sogo Osaka 12 SONGS GIFT
In Sogo's 12 SONGS GIFT Rabbit Chat, Ryunosuke tells that he enjoys drinking with Sogo. They did it many time, although none of them seems to remember what happened because they were too drunk. He thinks that Sogo gets more relaxed when he gets a little tipsy. Sogo also loves drinking with Ryunosuke.

Sogo Osaka Rabbit Hoodie
In Sogo Rabbit Hoodie Rabbit Chat, Sogo tells that for his birthday, TRIGGER went to IDOLiSH7's dorm to surprise him. Ryunosuke stood in Sogo's room, waiting for him to wake up so he could jumpscare him with a sign.

La Danse Macabre
"La Danse Macabre" is an alternate universe with IDOLiSH7. Sogo and Ryunosuke (now named Schau and Qual) are both in the "Unity Order" group, Qual being the boss.

Fanon
RyuuSou is neither one of the most popular ship of IDOLiSH7, nor a rarepair. This pair is classified as IDOLiSH7's 4th most popular ship on AO3, being Ryunosuke's most popular ship and Sogo's second most popular on the webside. However, this popularity is really visible only on AO3, the ship is way rarer on other media (fanarts, fancomics,...). The ship doesn't have a lot of fans in the West but is way more popular around japanese fans. This can be due to the fact that japanese fans has easier access to the Rabbit Chat in which most of the ship's canon content come from while western fans only relies on the anime.

RyuuSou fics tend to be extremely fluffy, the two characters being both shy, polite and think more about other than themselves. Most of the fanfictions deals with both parties having a crush on the other but not telling anyone because of their shyness. In a lot of fanfictions, Sogo or Ryunosuke keep their crush for themselves, believing it will either cause great trouble for their group or not believing that their crush love them back.

Fandom
FAN FICTION

Trivia

 * Ryunosuke and Sogo are both considered as the parent of their respective groups.
 * Ryunosuke borned in a modest family while Sogo borned as the son of the FSC president. They both reversed their status as Ryunosuke became a hotel maniac's stepson and Sogo fleed his family.
 * Sogo is 175cm while Ryunsouke is 190cm.
 * Ryunosuke once posted a photo of Sogo on social media for the younger man's birthday photobook.
 * They once took a bath together, along with Gaku, Yamato and Mitsuki.
 * Sogo has photos of Ryunosuke on his phone that he looks at to help him relax before performing.