someone who smokes, and not to preserve salmon. someone who actually inhales smoke on purpose to get a drug from the smoke, such as nicotine. a loser, a stinky butt-sucking loser.
dude, if you are a butt sucker, then you are just a stinky butt sucking loser. don't be such a loser.
Someone who slobbers on the end of a cigarette when sharing it with friends
"That Alex is such a butt sucker, this cigarette is fucking soaking"