The male protagonist who is the heir to the Mikadono Group. For him to take over, 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 a scar on his forehead from an accident when he was a kid, which caused him to lose bits of his memories.
In the last novels, he chooses Konoe as his lover, but also gets to know that she is also his sister. However, Shougo is not Kumagorou's biological son; for some reason, Kumagorou and Shougo's mother, Kanoko, were unable to conceive a child together and Kanoko gave birth to Shougo through artificial insemination with another man.