Yes!
And no. But there're really only two rules for BKO:
Never talk about doing illegal activities. I don't care what you say, but that kind of thing is disgusting, not to mention dangerous.
No fighting.
Other than that, you can do pretty much anything. I do ask that you keep your posts as tasteful as you can, though... don't just post some random garbage. I mean, aimlessness is fun, but if you're just trying to be funny but seriously failing... your thread will be locked.