I've wondered that about songhyel's works for a while now, because while I think they handle rape as a topic way better than others in bl, the scenes are quite graphic. but I wouldn't really say they're depicted merely for sexual gratification/for the reader to think it's "hot" like some other series.
so why do that?
what's to gain from showing how characters have sex (or rape)?
I'll argue that they're presented graphically so that there's a stronger contrast with the consensual scenes. graphically showing the characters' behavior/demeanor in different contexts emphasizes the emotional state and considerations of the characters involved. this last chapter and even the chapter prior where seong su got kidnapped leaned heavily on the shock and starkness of the scenes, yes - to the point where you might go "do I need to see all this?" but their respective focus and the actions portrayed in each reflects the POV character of those moments and their relationships to each other. as uncomfortable as it is, by showing how the new guy treats and views seong su during sex, and showing that they're primarily/only having penetrative sex, there's a strong contrast with what hyeondo/bonggu and seong su do, which is more exploratory, mutual, or focused primarily on seong su's enjoyment (not to mention that seong su initiates or invites or reaches out for it in those instances). it's easy to get caught up in the shock and even possessiveness of what boils down to "some guy stole my hole!!!" and how that ties into notions of "real" sex (which is penetrative, obviously! [heavy sarcasm]). while your suggestion is how I generally prefer things, it's notable that in showing everything in the latest chapter you can see that it's not only, or not entirely a painful experience for seong su have sex with the new guy (and I can see this having Implications). if you think about it, the way seong su is basically out of his mind with the new guy apart from doing what else he can to avoid impregnation + how he's visually presented in that chapter reflects how the new guy sees him (sex object?), versus how he acts in every other intimate scene with hyeondo/bonggu is quite revealing of their dynamics.you can apply this to ouroboros and lovesick dog and see how those scenes are used to flesh out characters and their dynamics even when they're intended to shock and dismay.
so I'm inclined to give some leeway about the graphic nature of the rape scenes because of what they yield in terms of characterization and character/relationship developments. that might sound odd, but I think this creator's use of their skill with expressions/expressivity and setting moods/atmosphere in those moments rewards a careful examination, even with the discomfort of it all.
Hmmm, you present a well argument and I have to agree, mulling over it myself I think, the SA scene are a lot more brief but they pack a punch so it makes it seem like they stretch out a lot more than they actually are. I have to admit it is something I’m rather skeptical about because of the whole nature of yaoi authors in general but I really want to believe they don’t do it for shock factor since they chose to opt out the snuff film. I feel like that was such a deliberate and thoughtful decision that helps me favor your argument.
yeah, given broader trends on this, the skepticism and wariness is justified. I brace myself even when I read songhyel's stuff because you never know when a creator is going to disappoint you on this, no matter their track record. I've been burned before ╥﹏╥
but so far, it's been okay! here's to hoping they take more creative liberties with omegaverse standards, and then I'll be over the moon!

I’ve been a fan of this author’s work and understand the visceral nature but this is really intense and gross and sometimes it feels like it crosses the boundary of gross to evoke empathy and gross for shock factor. Feel like some scenes could’ve been substituted, let the readers’ mind work and fill in the gaps instead of making it so graphic, like the detail of not showing the snuff film? That’s good and i wish there were more scenes substitutes as such (maybe focusing more on his face/hands to show how much pain he is in).