Since you didn't say they have to be the main couple, I'll add one of my favourites:
* "Sex pistols" (Yonekuni x Shiro)
(You can watch the OVA because their are the main there)
* "Ai no Kusabi" and "Genwaku no Kodou" are from the same author and the main(?) couple is Blond Top x Black haired Bottom
* Some of the author Yamane Ayano
* "Dos Obak......
