It's kinda fun. I like it anyway. You don't have to pay to get into the game, but there's lots of stuff there to buy.
The idea is that you have an "avatar" or a character that can move around in the world. There's lots of stuff to do there, most of which is free. But if you want to buy stuff (like fancy clothes, weaponry, tickle toys 🙂 ) you have to pay. That's where the charges venray was talking about come in.