Fukigen Kareshi no Nadamekata
The story of the hot, hot model's brother from the story where Keith aka Shingo is a werecat. Duty bound, the older brother married and had a child like his family demanded, but in doing so lost the chance to be with the man he loved, who stays with him as his servant. This is their story.
Kuroneko Kareshi no Aishikata
The continued cohabitation adventures of Keith aka Shingo and his hot, hot actor boyfriend. When the actor's elitist older brother shows up from England, he triggers Shingo's fear of abandonment when he threatens that his brother will leave Shingo for a wife to continue the bloodline. As expected, everything works out and there's a lot of sex. Also: the brother has an adorable son named Rio.
Kuroneko Kareshi No Nakasekata
Keith aka Shingo moves in with his hot actor boyfriend and they continue to have loads of sex.
Kuroneko to Kareshi to Ouji
This is the reality where Keith Kogane is a black housecat named Shingo (weird) and lives with a hot, hot model who is actually a leopard. In this, they babysit the leopard's nephew. By the same artist who drew the Maki story.
Fukigen Kareshi No Saraikata
The continuing adventures of werecats. We once again meet the older brother and his assistant, who are sleeping together but not *sleeping* together, so the relationship is experiencing turbulence. Lucky for these two, a wedding provides the opportunity for much-needed alone time. Unlike the other books in this series, this fell flat emotionally. Maybe it was my mood or what I'd read before this, but I couldn't wait for this to end.
Kuroneko Kareshi no Asobikata