Only if you consider his complete hijacking and near-derailment of the RP because he felt like it as the first offense.
That was Etch, not Madness. But they honestly both have their moments.
... I didn't see this post, but I'm not hearing good things and it doesn't surprise me TOO much. There's a limit to how far you can go with absurd events in a serious-ish setting, which quite frankly Madness has often seemed to disregard. The barfight worked! The random talking bear didn't. We had a talk about this, yeah. I'm not sure how much it helped...
I can't
entirely agree with NSFW content and fetishistic material being unthinkable for the RP, actually; MTG set up a separate board for it if need be, and even had Reimu sort-of mention it in the largely-omitted Day 5 content. It makes more than enough sense for some of the characters there to at least have interest in some objectionable sexual practices, so a complete veto doesn't quite work. The important part is keeping it under control, and actually following forum rules for here.
Since I kept thinking about it and we might as well take care of it now rather than later, here's some guidelines for NSFW RP content in rough order of priority:
1. Don't post it on MotK. Use a properly-marked link!
This should, really, be obvious. It's okay to make a post to point out offsite NSFW RP content as being relevant and available, but don't actually post the NSFW here.
2. Don't make it required reading. Make sure you can summarize all the plot-relevant content in a SFW way without glossing over important details.
There are a good number involved here (Sana, Nemo, likely others) that don't seem interested in NSFW content, period, and shouldn't be required to read some just to keep up. While such, let's say 'incidents' can be important to the story, don't make it so that specific NSFW details like specific sexual practices or the like are required knowledge.
Xan and Theorist have made a good example of how to do this successfully: I think they put together a detailed NSFW Day 5 segment with Youmu and Lunablade that was important about inspiring Day 6's wedding fiasco. However, the only thing you need to know about that is "Youmu and Lunablade had a sexual encounter as is mandated by magical girl practices; now Youmu feels guilty and insists that the two get married." No need for details about the actual sexual encounter, or what they 'used' during it.
3. Include warnings for specific potentially-offensive content in the NSFW posts. Loli, futa, tentacles, severe dom/sub, etc
Since posts here pretty clearly indicate that even people tolerant of NSFW content aren't interested in ALL types of NSFW content. So, note what people might want to skip even if they're tempted to check out the details of your erotica.
I have begun failing in being able to think, so I'll leave it at that.