Gotta say, I have absolutely no fucking clue what I'm supposed to take away from this story and I absolutely love it. It's got just the perfect blend of concreteness in the characters and abstraction in the plot. Perhaps it relies a bit too much on cliche for characterization -- but that's practically a staple of horror anyway, and a sad necessity given the apparent size of the cast.
I'd say that the unemphasized strangeness of the setting -- offhand mentions of cults, etc -- seem to work both for and against things. On the one hand, it's a bit slow to reveal that we're very much in a Twilight Zone-esque alternate universe for it to really land effectively. By the time we work out that this isn't the typical 'weird stuff happening in a horror movie' trope, but rather that we're in a weird alternate reality, I feel like enough time has passed that it has trouble landing a meaningful blow. It's not really disorienting to the reader, and it's not really impactful in a way that makes me question what I've seen. By the time the nature of the setting is revealed, too much has happened for me to really go back and review things in a new light. It's more of a, 'eh, that's really weird, I wonder where this is going and why the author is being so coy about the bizarre nature of the setting'. It certainly helps with the ambiance, but frankly I think the set-up was a little too slow and interrupted too much with the characterization. It's also not interlinked -- it doesn't seem as though any of the characters really depend on the strangeness of the setting, and I think that's a missed opportunity to knock out two birds with one stone. I'm not sure how it could have been done better, mind you, so this is more of an impression than a criticism.
Likewise, I feel like it's necessary to critique the eroticism of the work. Frankly, nothing much here is sexy. the brief asides to the suggestive renders aren't really presented in a way that makes them particularly hot or appealing. If anything, some of them come at a moment that interrupts the flow of the action. It seems like that's sort of intentional, there's a rhythm of 'characterization, erotica, horror, plot, erotica, horror, plot, erotica,...' -- so on and so forth. But, frankly, I don't know that it does the work any favors. The porn feels functional in nature, without a lot of effort given to playing things up. A few lines of dirty talk -- some good renders, too -- but then it's back to the action without much time spent lingering on the eroticism of the situation. Not much emphasis is put on the fetishistic aspects of what's going -- the eroticism of transformation, for example, with the machine. There's justa few lines about 'oh, my tits are bigger' and then boom a few side-by-side flasghes of imagery, and it's over. Nothing about sensitivity, how it feels, doubts and worries, running hands over everything -- it all needs to be a bit more drawn out and toyed with. That's really what the oddest thing about this story is -- it seems like you really understand toying with the audience when it comes to horror, but the sexuality of the whole situation is just thrown down on the table and left there out in the open. If you applied the slow, teasing care that you seem to take with presenting the bizzaro-spookiness of the setting to the actual pornography, then the story as a whole would be improved.
Alas, I think that ship has sailed. You've got too many things to do with Mel's body -- three routes in this most recent chapter doesn't leave a lot of space to drag things out, and a change in direction at this stage would be detectable and devastating to the flow of the story. I don't really know what to suggest as a remedy beyond telling you that it would be prudent to drag out erotic moments more and focus on sensation. Right now, it's all dialogue and it's just not cutting it for me. It's certainly effective at keeping things moving along, but it's certainly not arousing -- if that was ever the intent.
Honestly? I'd be rather happy if you cut out all the porn -- except, maybe, the Swedish girl, but that's a personal preference -- and just focused on this fucking peculiar setting and story that's going on.
I'm reminded of one of the other games on this site, That Intoxicating Flavor, in that I really could not give less of a shit about the naked women in your story, but god damn I want to know where this circus is headed.