If you can't stand one user here, you can ignore them.
If you can't stand a few users here, you can work out your differences.
If you can't stand a whole bunch of users here, you probably should take up roots elsewhere on the ol' interwebz.
I mean, if you literally can't avoid whoever it is because their posts are everywhere, it's likely the forums will fall eerily silent whenever you block them. Besides, the chance to bother someone is a sacred CYS right.