I'm not sure mangafan321 is getting the point of this manga, no disrespect, but I don't think s/he is. This is a very realistic manga depicting the gay leather scene in 80s' New York, so it's definitely not what you might expect from an average yaoi romance, but I felt more love here - real love - than I did in many of the sugar-candy, laminated, callow yaoi mangas. There is serious stuff going on here, psychologically and emotionally, but these couples are in it for the long haul and their devotion to each other is unmistakable.
Yes, there are some unusual circumstances that might border on squicky (like the, uh, consensual gangbang that mangafan321 mentioned)... But those scenes are unavoidable in a manga that wants to seriously engage with the BDSM lifestyle in eighties' America, before the whole AIDS thing really started having an effect. Stuff like this actually happened (and sometimes still happens) in the BDSM community, but that alone isn't what makes this manga rare. What makes this manga amazing is that it is all psychologically explained. The BDSM isn't superfluous or just smutty - it has a deeper meaning to the characters involved, a meaning that is explored with unusual and unerring delicacy. This is truly a gifted mangaka, who did her research and bravely confronted a very difficult issue. The art is INCREDIBLE, so realistic that it's kind of like watching a series of photographs, the textures and the way light hits the different objects and materials is so uncannily real. That makes the sex scenes and BDSM scenes ten times more affecting/powerful, since you can feel them. Uh. And somehow, you don't get squicked by them. Or I didn't, anyway. Because there was love in those scenes, and it was so deep that you immediately understood that these scenes signified near-sacred rituals that were being practiced for complex, personal reasons - not just for mere carnality.
Consequently, I would like to note that despite the constant sex, none of it is meant to titillate readers in the usual way, and I wouldn't call it pornography. Not at all. I mean, this isn't smut. PLEASE don't confuse it with smut. Each sex scene is actually a character study through sex, as in, it's more about the characters and their issues/feelings than it is about the sex, and it shows. The psychology is really the centerpiece, and the sex is simply the pedestal it stands on.
I hope that explains things! Please don't turn away from this manga because it's unusual; in fact, you should read it because it IS unusual - in fact there is no single manga out there like this, about this very theme portrayed in such a stunningly realistic and honest way. It's practically seinen, I mean, neither the art nor the theme are stereotypically "yaoi". I'm not even sure I should call it yaoi... It somehow gives off a seinen feel to me. Don't pigeonhole this manga as per standard yaoi expectations... It has so much more to it. So much more.