Mr. Comfortable
That one member in every group of friends who eventually becomes far too accustomed to taking advantage of their position. This is expressed in a number of ways, including but not limited to:

-- Shitting in another member's bathroom, except in an emergency.
-- "Bumming" cigarettes, to the point of simply taking them from a pack at their leisure, without asking, and conveniently "forgetting" their own pack at every gathering.
-- Drinking the beer from the pitcher of another, with zero reciprocation. Also applicable to joint smoking.
-- Showing up uninvited, simply due to the knowledge of another member being present.

These individuals will continue offending the group until confronted with their behavior. This will often lead to an indignant response, designed to make the person confronting them feel guilty, and continue to allow the behavior. An organized shunning, or even total group exile is another possible outcome.

Also; Miss/Mrs. Comfortable
"Ahh, goddammit, everybody hide your weed. Mr. Comfortable just pulled up."