Koizumikioda

Koizumikioda is the poly ship between Mikan Tsumiki, Ibuki mioda and Mahiru Koizumifrom the Danganronpa fandom.

Canon
During several segments of the Danganronpa 3 anime and other parts of the pre-SDR2 lore, the trio are shown to be friends. In the Twilight Syndrome Murder Case game, all three girls, with the addition of Hiyoko, are shown spending time together and having what appears to be a good time before they uncover the murder mystery. Once the body is discovered, Mikan begins to cry as Hiyoko makes fun of her. Mahiru quickly comes to her defense, however, protecting her from any more teasing.

Mahiru is shown during the anime spending time with Ibuki and Mikan both, referring to them as her 'closest friends.'

During the first chapter of the second game, Mikan falls over into one of her infamous 'unflattering positions' during the first motive. Ibuki harmlessly jeers over the fallen nurse, claiming that someone should take a picture while Mikan lies on the dining room floor in a provocative pose. Mahiru, however, scolds the onlookers and attempts to help Mikan to her feet and to brush off her embarrassment, telling her to be more careful next time.

During the second chapter of the game, Mahiru invites Ibuki, Mikan and Hiyoko to speak with her about the video game motive. Neither Mikan nor Ibuki attend, however, too busy with Sonia's girls-only beach trip. At the reveal of Mahiru's death, Mikan is shocked and horrified at her death, going so far as to blame herself.

In the third chapter of the game, Mikan succumbs to despair disease, remembering her past as the Ultimate Despair. Similarly, Ibuki also catches the despair disease, becoming 'gullible' instead. Due to the convenience of Ibuki's location and illness, Mikan then lures her to her death in order to be with her beloved.

After awakening from their comatose states in Hope Arc, Mahiru comes to Ibuki's rescue as the plays music to ward off the invading snipers on Jabberwock Island. Using her camera to blind one of the snipers, Mioda's life is saved, and the two share a high five.

Along with Hiyoko, the trio are seen at the end of Hope Arc on the ship off the island, seemingly sharing a pleasant conversation.

Fanon
This polyship sailed to the growing popularity of Band Aid, the trio's screen time together, and the tightly-formed friendships between Mahiru, Ibuki and Mikan creating the need for an OT3.

While these three are often not shipped together in a three-way romantic pairing, some people who were fond of Band Aid, Snap Shot and Photo Album alike believe that the three would be happiest in a polyship.

While this ship is sometimes overshadowed by Soapies on Mahiru's side, it is typically believed that at the very least the trio could make a happy group of friends.

Fandom
Koizumi/Tsumiki/Mioda on Fanfiction.Net

Trivia

 * Each member of this poly ship dies in their game, Mahiru in the second chapter, and Mikan and Ibuki in the third, only to be revived during Hope Arc.
 * With the addition of Hiyoko, the members of this polyship were the first to discover the dead body of Natsumi Kuzuryuu, and to star in Twilight Syndrome Murder Case.

Variations
Photo Album refers to the ship between Ibuki and Mahiru

Snap Shot refers to the ship between Mikan and Mahiru

Band Aid refers to the ship between Mikan and Ibuki