Yeah, hundreds of guys stalking them. A j-forest girl I once drilled (paid) had more than 4,000 male ''friends'' and a hundred or so female ones. Unless they have met you in person and have been wooed by your charm, they'll just think you're another horny creep and won't take you seriously.
To the OP: Do guys actually hang out at parks to get laid?
Plenty of money honeys in bars. From personal experience, it's less time-consuming and often cheaper to get your horniness with that girl resolved there and then (and less likely to get into trouble with a significant other), but if you you wish to chat with them online, set up a ''wanchai'' fb account. Meet them, exchange fb details, and go from there. And be sure to hide your friends list from friends, so they don't know who else you're chatting with. A lot of effort, however, to get laid and most will only be interested if there's possibility of bf/gf relationship.