Responses
That is young Miyauchi in the picture. Kudou's father was his mentor.
Jirou and miya are half siblings. Before Jirous mom got married to Jirou's dad, she got a maid pregnant. That baby was Miya. Kudo's dad, the head butler that time, took him in, taught him and left them with Aoi's family. The kid in the picture with Kudo's dad is indeed Miya.
In the end of chapter 6 it's shown the picture of kudo's father and a women which looks like miya.
But i know that miya and jirou is brother from his father statement, but the pocture is kind of misleading too.... i'm so confused(⊙…⊙ )