Seiha Shiunji

As the second daughter of the Shiunji family, Seiha is a third-year high school prodigy who ranks first academically across the entire school and is known as the 'Princess of Rationality,' while also serving as the science club president. Composed by nature and driven by a constant pursuit of efficiency, she approaches everything with methodical precision. Upon learning the truth about her bloodline, she channels her researcher's spirit to rationally examine her own emotions, using the analysis of romantic feelings as a pretext to actively close the distance between herself and the protagonist, Arata.