Got BBFS from J Suzuka at Ginza a few months back. Was drunk, plowing away with a rubber on didn't work very well, so I just asked 'no condom?'. She said $100, I said I only had $50. She agreed. CIP was not discussed, but nor was it resisted. Got tested a few months later, all clear.

I got the impression K Nana maaaaay be open to this, though I myself didn't ask. When the moment is right, I would suggest you just ask, OP. Don't make it a big deal - just a casual q. Nobody is gonna kick you out for asking that, I don't think.

P.S. For me this was the first and last time doing BBFS with a hooker. Should NOT, repeat, should NOT have been done. Won't happen again.