If I understand your slang correctly, it's not something that would bother me psychologically, meaning that I wouldn't be skeeved out by the thought of making it with a girl who is on her period.  But it is a health concern for me, and for that reason I'd have to pass.  This is one situation where the big head would overrule and veto the little head without question.  It may sound irrational to some, but I just wouldn't take the risk.  I would suggest that we just engage in some mutual touching and kissing instead.  I'd use the trusty manual release valve at the end.

trust me, it's been known to happen

Sometimes a lady will get her flow, before her scheduled date. It happens. It sucks. But it's just a part of life.

When she already has it, before she sees a client, she should always be honest and upfront w/the client to let him know, before making the appt.

I've had the unexpected flow happen, during a session, and thankfully the men that I had seen were understanding, and we were able to find other ways of continuing our sessions.

Personally, I would always cancel the appt., when the flow came, before any appt.s, unless it didn't matter to him. But, I always gave him the choice. I would always take the week off, as a vacation week.

that goes up into the piping and catches the blood so that no one need know.

Several providers have told me about this.

At fine pharmacies everywhere.