Just a follow up, because I just ran into this- there's lots of women posting or responding to personals on metropolis that are prostitutes of some sort or other. I responded to one looking for a short term thing, "business traveller okay", and she turned out to be a rub-and-tug girl who wanted 2 man yen for 90 minutes of 'sensual massage'.
Other than that, my recent adventures with metropolis classifieds have gotten nearly 100% hit rate on girls looking for hookups, dates, and friends (I'm not necessarily just looking for random sex), although 2nd emails drops down to maybe 40 or 50% since I probably weigh at least twice as much as some of these girls...