Much like
@lapdog2001 said above, it is all a matter of context. If the erection is involuntarily and was only caused by touching a particularly sensitive area then I would give that person a pass. There is also the possibility it could be caused by the man having sexual thoughts about women (as we do quite a lot when we are least expecting it
) and it is just coincidental with the massage. But if the man's erection was caused by thinking about the guy giving him the massage, particularly when he touched a certain area, then while I wouldn't go so far as to take away his straight card, but he definitely has some bi-curious inclinations, though if this site is any indication, he'd likely deny it.
I've had quite a bit of massages from both men and women with all but one for therapeutic reasons concurrent to injury and none of them turned me on. While some may have felt sensual, none of them felt sexual and only once did I get an erection and it was not due to the actual massage, but because the woman had her crotch (with slightly visible camel toe) inches from my face as she was doing my neck, so it was purely a mental/visual reactionary thing. Even the one non-physical therapy couples massage my wife and I received did not arouse me despite it being more sensual than the others and including my whole body versus the others that limited the areas to my back and neck and only required me to remove my shirt.
As far as my preference of gender, I really don't have one for the most part since as I said, I don't consider an ordinary, professional massage sexual. Both have their advantages depending on what the massage is attempting to accomplish. For a simple feel-good, stress-relieving massage I do lean slightly more towards a female and the lighter touch; while I've found for really tight muscles or deep tissue injury, the usually stronger grip of a male is more effective for pain relief. But these differences are small, so it really comes down more to the individual therapist than their gender.
