I hope most gentlemen I know realize that they can always rely on me for a reference. I think some ladies prefer if you ask them first, but I don't particularly mind.
I agree with Vanesssa, 90% people I see offer a reference, and the other 10% make a great introduction, and usually give me some kind of personal information to cross reference, or ask them to check into a 4/5 star hotel and give their check in name for cross reference. Also, a really nice and genuine introductory email helps a lot, so I can get to know you a bit first, before even checking references. I like to know a lot more than if someone is simply safe or respectful. Extra information helps build trust, interest... and often is the beginning of any chemistry that might arise.
From my perspective, because I have another, conventional profession in a conservative institution, I'm thinking really of discretion as well as general safety. For example, I would not want to accidentally meet a colleague or family member!
I could see how some fellows might feel a bit shy about asking for a reference

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