A renaissance man/woman of horrible things. A Buttbag is a person who is part attention whore, part pretentious hipster, part fake yuppie, part drama queen, part conceited douche and part self-righteous asshole. Perfect examples are: Kanye West, Tom Brady, Christina Aguilera. A great fictional example is Sarah Marshall from 'Forgetting Sarah Marshall'.
Did you see Aunt Jane's daily Facebook posts about how she's in mourning for her dying father....but according to her he's been dying for 15 years AND she threw in something about being a great caregiver and how everyone else is a horrible person. Man she's such a Buttbag.
A condition of tightness or numbness in the testicles that is felt after fully inserting them inside another person's anus for a prolonged period of time. The intensity and duration of buttballs is dependent on several factors, including but not limited to the size of one's testicles, blood pressure, tightness and dilation of the host's anus, and duration of insertion.
"Damn Tone, you dunked yo nuts in that bitch's ass for over 20 minutes! You must have a serious case of buttballs."