Sounds like a support forum question, but:
1. Home (hover)->Account->Manage your privacy settings
or
2.If they leave a note for you, you can block them there (option under the note).
or
3. If playing live chess, in the chat window you can right click the opponent's handle and the option is in the drop-down menu.
There is a certain individual who seemed nice at first. he has become annoying, rude and flooding me with games that for some reason I cannot cancel. How can I unfriend and block this person? The cancelling of game requests issue is not just with this individual if I get a game request I have to play it or just sit there. Can someone help please?