I think they have a "safe word" of their own. its different than what is common but I think it works for them. if you notice before the seme proceeds with what he is doing he says what he is going to do and asks the uke what the answer is, the uke then answers yes or no. and the seme asks this quite often throughout their play, reestablishing consent.
however I do agree that they should have another safe word, as this way wont work for all situations. but I think they can do this for now and cross that bridge when they get to it. (▰˘◡˘▰)
Ikr. I swear I saw a safeword tag, but no safe word is mentioned. There is no proper BDSM without a safeword, and that’s why reading any “BDSM” work that doesn’t practise proper BDSM turns me off. It feels a bit rapey or abusive. I do like this work though, I’m just disappointed BDSM is never portrayed properly in manga and elsewhere (I’m looking at you, 50 Shades of Crap).
I like it so far but they really need a safe word! It makes me feel uncomfortable because it seems to me that the uke is taking way more than what he was prepared to (considering he doesn't seem to really know BDSM)...