https://www.mangago.zone/read-manga/bj_alex/ <- side ch 7 specifically!
though yaoi w/ actually established safewords :00, those are hard to find by themselves D: but following this thread c:
I think these mighttt have what you're looking for/at least more bdsm discussion than the regular but not completely sure
https://www.mangago.zone/read-manga/aporia/
https://www.mangago.zone/read-manga/blood_bank/
https://www.mangago.zone/read-manga/my_partner_s_tastes_and_fetishes/
aaaaa i have already read all of them but still thank you so much for linking them
D: no problem! hopefully someone else comes along w/ more suggestions
any yaois with a sub/dom drop? or a bdsm play where sub/dom used a safe word? i just wanna see a bdsm play gone wrong