The group never interacts in its entirety in canon. However, they are implied to often hang out together in the non-canonical bonus mode of Danganronpa V3 - Ultimate Talent Development Plan.
Throughout the Prologue and Chapter 1, it is mainly Kaede Akamatsu and Shuichi Saihara who interact with each other, bonding with each other, encouraging each other not to give up, coming up with and executing together their own plan to take down the mastermind, investigating the crime together, and having heartfelt moments during and after the Class Trial. However, Kaito is also shown on several occasions to look up to Kaede as a leader and to share her positive and motivational views. Meanwhile, while Kaede and Shuichi had their own plan to take down the mastermind, Maki was included in Kaito's group planning their own way of dealing with the motive. Being the protagonist at the time, Kaede can also befriend all three of them in their separate Free Time Events.
Following Kaede's death, Kaito decides to take care of Shuichi and help him with his grief. As a result, the new friendship between the two becomes one of the central aspects of Chapter 2. Kaito promises to share Shuichi's burdens and the responsibility of his decisions, begins his trainings with him, and investigates the crime with him. When the suspects are narrowed down to Kaito and Maki Harukawa, the former claims to believe in her, which inspires Shuichi to believe in them as well and take a look at the crime from another perspective, which eventually helps the group find the actual culprit.
With her true talent as the Ultimate Assassin being revealed and alienating her from the group, Kaito decides to include Maki in his trainings with Shuichi, not wanting her to be alone and full of self-hatred. This becomes the starting point of the close friendship between the three of them. Maki asks Shuichi whether it's alright to have feelings for someone (referring to Kaito), recalling how fond he was of Kaede. All three end up on the same side of the argument after the introduction of Angie's Student Council and the motive. Since Kaito's feeling sick, he ends up missing one training. Maki and Shuichi also investigate the crime together during this chapter.
The bonding and trainings continue throughout Chapter 4, including one missable Special Time Event, until Kaito and Shuichi's friendship is put to a test during the Class Trial, after Kokichi Ouma challenges Kaito's beliefs about trusting others when the evidence points out to an otherwise innocent Gonta Gokuhara being the culprit. This ends in Kaito avoiding Shuichi for the time being.
Throughout Chapter 5, Maki attempts to make her two friends make amends with each other. After Kaito is kidnapped and imprisoned by Kokichi, both Maki and Shuichi are motivated to save him. Shuichi's friendship with Kaito is also restored at the time. It's later revealed that Maki acted on her own to save Kaito from Kokichi.
With Kaito's death, the only members of the group who remain alive are Maki and Shuichi. They continue working together, along with the other remaining survivors, in order to end the killing game for good. They also recall their memories with Kaede and Kaito at several points in the last trial.
Like Kaede in Chapter 1, Shuichi can further befriend all the members of the group through Free Time Events, although the ones with Kaede can only be played in the bonus mode, as a result of her early death in the canon. Shuichi can also have Love Hotel scenes with all three other members of the group, with Kaede's one, once again, being achievable only after finishing the main game.
In the non-canonical bonus mode, Ultimate Talent Development Plan, Kaede and Shuichi have 4 events together, Kaede and Kaito have 1, Kaede and Maki have 2, Kaito and Shuichi have 4, Kaito and Maki have 3, while Maki and Shuichi have 1. Throughout the events, the friendship between all four of them, including the Training Trio dynamics of three of them, are frequently mentioned.
- “When things are bad, me, Maki Roll, or Kaede will help you carry your burdens. As long as you understand that, you can get stronger.”
- — Kaito in his winter event with Shuichi in Ultimate Talent Development Plan.
- Kaito – “Nah, I've got a message from Kaede. She wants to talk about the promise you made with her. I dunno what kind of promise it is, but...since when were you guys so close?”
- Maki – “We're not close, and I wouldn't call my arrangement with Kaede a promise, either. She offered to play piano for the kids at my orphanage. That's all.”
- Kaito – “Oh, that's a great idea! She's amazing at the piano!”
- Maki – “But... I left that orphanage years ago. Kaede thinks I was the Ultimate Child Caregiver at that orphanage before I came here, but...”
- Kaito – “Hey, there's no reason you can't go to the orphanage, right Maki Roll? So just take Kaede there with you. For the kids living peacefully there you worked so hard for... Let them hear Kaede's music.”
- Maki – “That...might be good, but...”
- Kaito – “Oh! I just had a great idea too! How about me and Shuichi tag along? Yeah! Let's do it! If Shuichi's with us, I bet Kaede will get all psyched up!”
- Maki – “You want to tag along...and bring Shuichi?”
- Kaito – “Yeah! If there are any problems, Shuichi and I will help out!”
- — Kaito and Maki's conversation, showing the group's dynamics, in their Friendship Event in Ultimate Talent Development Plan.
The ship sailed as a result of the close friendship formed between all four characters at some point in the story. While the group includes some of the most popular ships in the whole franchise, namely Harukaito, Saimatsu, and Saimota, shipping all four together is rare. The fact that polyships, especially including more than three characters, are not as popular in the Danganronpa fandom also did not help to increase the ship's popularity.
The ship is more commonly portrayed as a friendship between two couples, Harukaito and Saimatsu. Fan arts usually show the group on double dates with such dynamics, hence the name of the ship. Finding art that portrays all four being romantically interested in each other is much rarer. Sometimes, fan arts show the group with Kokichi Ouma, another main character of their game.
However, the popularity of the ship is increased with the aforementioned fair number of fan art. Certain gameplays might also help to further fuel the ship. For example, in his letsplay, NicoB portrayed both Kaito and Shuichi as romantically interested in both Kaede and Maki, the latter two being portrayed to return the feelings.
- Kaito is the only member of the group who wasn't a playable character at any point in Danganronpa V3. However, there were still scenes from his point of view, such as the one when he's revealed to be sick for the first time, at the end of Chapter 3.
- The group, along with Kokichi Ouma, could be considered the main characters of Danganronpa V3, with Kaede being the first protagonist, Shuichi being the main protagonist, Kaito being a deuteragonist, and Maki being the main heroine.
- Half of the group consists of culprits (although Kaede's plan is later revealed to have failed and it was actually Tsumugi who killed Rantaro), while the other half includes two of the three survivors.
- Harukaito refers to the ship between Kaito and Maki
- Kaimatsu refers to the ship between Kaito and Kaede
- Nursery Rhymes refers to the ship between Kaede and Maki
- Saimaki refers to the ship between Maki and Shuichi
- Saimatsu refers to the ship between Kaede and Shuichi
- Saimota refers to the ship between Kaito and Shuichi
- Training Trio refers to the ship between Kaito, Maki, and Shuichi