Twomiki

Twomiki is the het ship between Ultimate Imposter and Mikan Tsumiki from the Danganronpa fandom.

Canon
Although the two have little to no interaction in Danganronpa 2, their relationship gets to be developed more in Danganronpa 3: Despair Arc.

In episode 5, after noticing Ryota Mitarai works so hard on his anime that he began neglecting his health, Ultimate Imposter forcibly takes Mikan Tsumiki and brings her to Ryota's room, knowing that thanks to her status as the Ultimate Nurse she'll be able to nurse him back to health and trusting her with his and Ryota's secret. She assumes that the Ultimate Imposter will either want to kill her or want sex in exchange for knowing too much, but the Imposter quickly assures her that he trusts his classmates. Mikan begins to cry, saying no one has been this nice to her yet. As a response, Imposter tells her to have more confidence.

In episode 7, Imposter goes away with Mikan and pins her against the wall in a kabe-don fashion, in order to tell her about Ryota Mitarai's disappearance. Mikan promises to look for him, which eventually leads her to meet Junko Enoshima and Mukuro Ikusaba. Meanwhile, the classmates start wondering where the two could have gone, with Kazuichi Souda and Teruteru Hanamura having some suggestive ideas, which the latter shows with an example of a donut and a banana.

In episode 8, after Mikan skips classes again, when Nagito Komaeda reveals he had seen her going to the west district, Ultimate Imposter reacts very aggressively, asking him if he's sure about that. Nagito himself points out he doesn't remember Imposter as this type of character.

Ultimate Imposter looks for Mikan along with the rest of the classmates. He is seen to be very worried about her, to the point of not being hungry, unlike usual.

In one event in the bonus mode of New Danganronpa V3, Imposter brings Hifumi Yamada to Mikan after the Ultimate Fanfic Creater was overworking on his doujins. He comments that he had Mikan help his friend (Ryota Mitarai) in a similar situation, meaning their friendship in this timeline is similar to the one from Despair Arc.

They also interact in another event of said bonus mode, where they prepare a party for their class. Imposter tells Mikan to just enjoy the party and mentions that he thinks all of their classmates are equal, including her, which touches her. When she leaves to go get the others, he tells her to be careful not to trip.

Trivia

 * This is the only relationship between Danganronpa 2 characters that gets a fair amount of ship tease in Danganronpa 3, but wasn't referenced at all in the second game. This may be because the circumstances that let these two form a closer bond with each other (Ryota Mitarai getting sick) was missing in Danganronpa 2, as Ryota did not participate in Killing School Trip; as well as due to Imposter's early death.