No, but roleplaying does add another level to the game. If you want to just go out and kill things, you're more than welcomed to, but if you want to roleplay, all you have to do is find someone that wants to roleplay with you. What you roleplay is up to you. RPL's (Roleplay leaders) will even give out award points to people that roleplay (just so long as they know about it so you may have to drop them a line or post on the website) and you can use those points to buy things that only roleplayers can have.

Current RPL's are:
Hesara
Lucrete
Riley
Natalya