Seirati

Ryoko is the het ship between Ryota Mitarai and Seiko Kimura from the Danganronpa fandom.

Canon
Although they're both leaders of respective Future Foundation's divisions and they both participate in the Final Killing Game, the two have no interactions with each other on-screen. This is because Seiko was expelled during Ryota's first year at Hope's Peak, which he also spent on drawing anime in his room and skipping classes, as well as becasue Ryota joined Kyoko and Tengan while Seiko focused on her conflict with Ruruka and Sonosuke.

Fanon
Although they never interacted in canon and both have their own more popular ships, some fans ship Ryota and Seiko together. The reason for that is their "Medic Girl and Ill Boy" dynamic that they share with Mimiki, their common status as the "cinnamon rolls", as well as both of them wanting to save everyone, Seiko with her medicine and Ryota with his anime.