Simple question: Do you prefer (adult!) games to have music playing in the background or to play it silently?
I personally mute the music in every adult game as soon as I hear the main theme. Why? Because it sux most of the time. If there are two sliders for music and sfx, I tend to keep the sfx, but not the music.
I know everybody has their own taste, but if you know a adult game that could prove me wrong, please post it^^
The easiest example I can think of is Being a DIK. Great job with the music in that game. The music fits the theme for each scene, you can configure which stuff you want to hear if you want, switch tracks manually if you want, etc. I found that the music really enhanced the experience though so I just left everything at the default setting.
There's also the issue that you get a different experience if you can replace some of the narrative and/or dialog with music or sound effects. For instance I would rather actually hear a knocking sound than a dialog popup that says "knock knock" or whatever. Also for something like a sex animation, instead of having a bunch of fairly pointless dialog that mostly just includes ooh, ahh, oh god, fuck me, whatever, it's nice to just have some music play in the back ground while I enjoy an animation without having to click through dialog.
Sometimes dialog or narration is not the best way to get your point across.