When they first met, Shuichi realized who Kirumi really is and was surprised when she mentioned how popular she is because of her talent. Kirumi seems to care for Shuichi, willing to obey him the same way as the rest of their classmates. She even told Kaito to stop hurting Shuichi after the first trial ended. Kirumi was really disappointed when Shuichi pointed her out as the culprit in the second trial. Kirumi still hasn't accepted her fate and tried to vote Shuichi as the culprit. Shuichi was depressed and upset when he got to see another friend getting killed. He seems to be also one of those people who tried to tell Kirumi to run away from her execution.
In her Free Time Events with Shuichi, Kirumi saw a lot of potential within him and wished to serve him. In the bonus Love Suite scene, Shuichi has a role of being Kirumi's master, with whom she has fallen in love with. At first, she believes these feelings are inappropriate but Shuichi convinces her otherwise. It's shown in the fantasy that Kirumi still sees Shuichi as the Ultimate Detective being her ideal partner.
In one of their event they shared in Danganronpa S. Both Shuichi and Kirumi greeted a good morning to each other, Kirumi then advocated Shuichi for a beverage for breakfast. Shuichi answers with Tropical Juice, but as soon Kirumi was about to go and prepare it, Shuichi stops her. He tells her that she doesn't need to serve their every need, which Kirumi asks what made him say so. Shuichi states that it's an important time before their graduation, stating that she should use this time for herself, seemingly concerned. Although Kirumi tells Shuichi to not worry about her, his thoughts were appreciated. Kirumi managed to convince Shuichi that he shouldn't hesistate to rely on her. Which Shuichi apologies to her, Kirumi was fine with it and says that she's delighted for his compassion. Kirumi then gives Shuichi his Tropical Juice, stating that his breakfast will be ready momentarily. So he thanks her for it.
Sairumi sailed because of both Shuichi and Kirumi having different personalities that somewhat match and balance out each other.
Shuichi is a timid, anxious person who has trouble communicating with his peers, whiles Kirumi is a independent person who's willing to fulfill her peers every request. Some people may think that because of their personalities that they would not be capable of having a stable relationship when that's not the case, If both Shuichi and Kirumi were not in the situation they were put in they would've been able to grow closer and form a bond with each other. The pair is considered to be a rarepair due to the lack of content because they are outshined by their rival ships, those ships being Saimatsu, Tojoshi, Saiouma, Amasai, Kirukiyo, Saimota, and Amojo.
- Kirumi's relationship with Shuichi on Danganronpa Wiki
- Shuichi's relationship with Kirumi on Danganronpa Wiki