How many have you slept with? Because that's the number of women you should have slept with by 25.
It's a sad fact of human nature that you can be doing nothing but getting busier than Humpty from Digital Underground could ever dream of (for the record, in a Burger King bathroom is intensely uncomfortable and I don't recommend it), and you still will feel like you're not having enough sex. You're probably terrified that you're weird or something because you haven't gotten x number of sexual partners, x being some number far more than you actually have. You're not. You're perfectly normal.
The key thing to remember is that it's not a competition. Anybody who tells you otherwise is a douchebag, and also probably lying about how many women he's slept with. If you're not emotionally ready to sleep with somebody, you shouldn't be hitting the bars looking for love.
Everybody gets around at their own pace; some of us are just faster paced than others. Look for what you actually want, don't try to hit a quota that doesn't exist.
I won't lie, though, if you sleep with twenty women, it's true you do get a t-shirt in the mail. Just who it comes from, and how they know, nobody's really sure. It's sorta creepy, actually. Shirt's comfy, though.
I love the tag "pickup artists are douchebag", I loathe the Seduction Community. Great answer Dan, can't wait to get my t-shirt lol.
I would actually prefer a guy who's slept with a small number of women over a big number. It means he's not a player, and is less likely to have some gross STD. He's more likely to see sex as an intimate thing instead of just an impulse to bang someone you met at a bar. Why women would want a guy who's had a lot of partners I dont know. I want a guy with experience of course, but experience just comes from having sex over and over. There's no need to have sex with a new girl each time to be considered experienced.
Don't do it cuz you feel pressured, do it because you love her. Hell don't even do it then, hold out longer to let her know that she as a person is more important than you reaching some nonexistent, and probably ridiculous, number.
Testosterone......