Shigure is Akito's most loyal servent.
When he was young, he had a dream about a woman. This dream was shared with Ayame and Hatori (all three had it). Akito is the key to making this dream real, hence why he works so diligently for Akito.
Shigure had a romantic affair with Kana's best friend, even when he knew that Mayuko was also in love with Hatori. He broke up with her after Hatori made Kana forget, though Mayuko's memory was never erased, despite being told that Kana's had been. Also, in an odd twist of fate, Mayuko is Yuki, Tohru and Kyou's homeroom teacher in the manga.
He is indirectly responsible for what happened to Hatori's eye and Kana's memory loss. He set up their meeting with Akito, despite knowing what would happen.
He told Mayuko that Hatori had moved on from Kana, lying to her.
Shigure often refers to the group living in his house as "tools". He talks about his "tools" mostly around Hatori, who gives him sage lectures every so often, but never tries to stop him. Akito is also considered a "tool".
In the recent confrontations between Akito and Yuki, Shigure commented that soon they would know who really is the "idiot". It is assumed he is refering to Akito.
Akito comments how much Shigure used to love him, but seems to be less satisfied with his attentions lately, mentioning that he's still thinking about "that woman".
He has some kind of possible romantic attatchment to Rin. They get very intimate in one scene they are alone together in.
Could he be the reason Akito put Rin in the hospital and not Haru?
Kagura - (Not much is changed about her, honestly)
Rin is living with Kagura and Kagura's mother.
After what happened to Rin and Kisa, Kagura's mother won't let her go to things if Akito will be present, fearing she will be harmed.
Odd, considering how much Kagura openly cares for Kyou that she hasn't been harmed yet, isn't it?
Momiji - (very little, may add more)
In the manga, Momiji is half-German, from his mother's side. He even speaks a little German.
He tries to protect Tohru from Akito and gets punched for it.
Hatori - (very little, may add more)
He shared the "woman" dream with Shigure and Ayame.
He has had meetings with Mayuko.
He strived to help Kisa because he hadn't been able to help Yuki when he stopped talking. She reminded him of Yuki.
He was dating Rin and deeply cares for her, despite her problems.
His feelings for Yuki are later confirmed as more teasing bestfriend-ish than shonen ai (especially since he is so in love with Rin).
He is unwilling to give up on Rin yet, despite what Akito did to her, and despite the fact that she doesn't seem to understand how much he cares about her.
Rin breaking up with him brought out Black in full force.
No information is known on Hatsuharu's family, but it is assumed he is under Hatori's guardianship, like Momiji and living in the main house itself (Yuki visits him once there, despite his hatred/fear of the main house).
Ayame - (lacking some information)
He sold out his brother for his own freedom and knows it. Part of the reason he tries so hard to make it up to Yuki.
The dream he shared with Tori and Gure scared him into tears.
He designs clothing as a way to "make something".
None at this point.