A while back I got several of these. I sent the sender a polite reply to the effect that I don't "date" strangers over the I-net, and that they shouldn't either as it is not only inappropriate, but it is unsafe, too. I also mentioned that I don't engage in same sex dates--the sender was my gender, and did appear to be foreign. I also got the impression that the person was trying to set me up for some sort of scam. I have not had a problem for a while now. I don't recall if I found a way to block the sender, or if they just stopped, as this was some time ago.
Try a polite refusal email response. If that doesn't work, do report it. Good luck.
Remember, we on the spectrum are all:
A Different Drummer
If a man does not keep pace with his companions,
Perhaps it is because he hears a different drummer.
Let him step to the music which he hears,
However measured or far away.
--Henry David Thoreau