Natural9,
Bettheworld is not a post-up sportsbook. It is a service for independent local bookmakers
to have their players wagers processed offshore. So it would depend on who it is that is inviting you to play there. The person who is trying to set you up is trying to set you up as his player and he would be the one booking and paying you. The best advise is know who you are dealing with as he is the one responsible for paying you.
BookieSolutions