LW 1 - There's nothing you can do about someone else's behavior. Just block him, and you won't have to see it.
LW3 - It's always depressing to see white people try to justify their complete disregard for the feelings of minorities, if it gets in the way of "their fun".  The fact that you are so entirely unconcerned for the feeling of your co-workers, and that you consider their feelings, not only a waste of time, but literally offensive to you, kind of tells us all we need to know, doesn't it? Here's a news flash - you don't decide what's offensive to other people. Sensitivity to and concern for the feelings of others is a sign of maturity and class.  So what do you think a lack of it signifies?