A Sean Beaner is a term used to define the erection that a heterosexual man gets while watching Sean Bean act. It is perfectly normal for a man to get one and is brought on by a combination of Sean Bean's rugged handsomeness and his extremely unique method of acting.
Dude, I'm totally straight, but I had such a Sean Beaner while watching Game of Thrones last night.
Friends who are known for constantly bitching about the onslaught of illegals from Mexico.
Oh shit, here comes Larry. He's one of my friends with beaner fits so we are sure to get a forty five minute lecture about too many Mexicans in the United States.