Well I don't really care about that,Okiya/Akai can have all the girlfriends he wants...I just like to watch how their interactions change...
Even if they don't end up together,I like the way the relationship is established,and Shiho/Okiya interactions are slowly changing(well I don't want to spoil anything)...
That's basically why I loved Aicon in the first place,because their relashionship changed slowly,they became closer...Even if they are not "lovers",they are interesting to watch when they are together.
This is also why I don't like AixMitsuhiko as well,we actually don't see an evolution in their relashionship...Ai doesn't show interest on Mitsuhiko yet since he's a child,something eventually will happen when he'll grow up,but for now he's just a friend for Ai.And I doubt Gosho will make a manga with the grown up DB to show their relashionship ...