What??? How have you guys never known what the word "bugger" meant? Its even made its way into American pop culture:
"Very well, where do I begin? My father was a relentlessly self-improving boulangerie owner from Belgium with low-grade narcolepsy and a penchant for buggery. My mother was a fifteen year old French prostitute named Chloe with webbed feet. My father would womanize, he would drink. He would make outrageous claims like he invented the question mark. Sometimes he would accuse chestnuts of being lazy."
Most people here probably recognize this quote. If not, it is Dr. Evil's speech from the first Austin Powers. I hear Americans quote that all the time. It means his dad really liked engaging in anal sex.
Less antagonistic version of jerk or douchebag??? It is a really crass word. Even Webster's American dictionaries list it as vulgar slang.