Shougo Mikadono (帝野 将悟/Mikadono Shōgo) is the protagonist of Kono Naka ni Hitori, Imouto ga Iru!.
The heir of the Mikadono Group, in order for Shougo to be able to inherit the cooperation he needs to graduate from school as well as finding a life partner. However, things become complicated as he learns that he has a younger sister who is watching over him as well as attending the same school. He has scar on his forehead from accident when he was kid and caused him to lose bits of his memories. After Konoe confesses to have been the one calling him. Miyabi reveals that the reason she couldn't attend Kumagorou's funeral was because of the Miryuuin entrance exam This leads Shougo to think that he might actually have a sister living somewhere else. But it is revealed that Miyabi is his sister was lying about the exam being on that particular day.
It is inferred that Shougo will one day propose to Konoe, and the two will get happily married.
Shougo has been known as a kind and caring person ever since he was young, and it is because of this attribute that helps him making friends and attracting girls easily.
Shougo is a clever young men who is fully able to unravel the mysteries surrounding him using deduction; and though Shougo at first did not wish to inherit the Mikadono Group, he nevertheless possessed a business acumen.