I agree ngl. I don't like sa between couples as I see it as totally unnecessary for the story and their relationship as it's yucky, but considering the points you've mentioned it's not the same as sa in regular stories where the couples are human. I'm lowkey enjoying side chapters as I've forgotten reading that part so I'm not harboring any hard feelings towards daewoo ┑( ̄Д  ̄)┍
maybe i'm just being a daewoo hater but he lived as a human. sure, they're still an evil doppelganger and a former incubus/devil pairing but they can still feel guilt on other things as portrayed in the story so why did the author brushed off the rape easily? it's like taking that matter half-heartedly. also, the rape is very unnecessary and quickly forgotten in the main story so to see these two together in the side stories leave a bad taste as a reader. just my two cents as a daewoo opp ( ̄∇ ̄")

I find it so interesting how everyone hates Daewoo. From a human perspective yes he's a piece of crap. However it's worth considering the incident in question was between a human doppelganger and a devil. The author made a point to mention that Joon was a former incubus to sort of justify him "getting over it". Joon was much more upset over Daewoo killing people than getting assaulted himself, because similarly going after unconscious people is what he used to do as a job (ch.52). Just my personal thoughts. I figure readers can enjoy the story more if they understand how the author has rationalized this pairing. Hopefully the next chapter(s) can offer some insight as well.