As Jim says - think back through - why do you need to tell her?
Is it because you suspect she will treat you inappropriately in a "hand job" or "blow job"?
Well, if the Name of the Game is casual blow jobs, being a "safe" substitute for uncommitted intercourse and that is indeed what you expect to do, well apart from getting moving right know with the stretching we describe here, you probably will have either to risk being "manhandled", or explaining to her that your foreskin does not come back and requires a slightly different and more careful form of attention.
Can't have it all - or at least, not in a hurry. Are you starting with the stretching now?
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