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3.
having sex with fat animals.
Ewww. I can't believe you love fat animals. your obestiality sickens me!
by moose123 July 01, 2011
 
1.
A pun combining the words obese, and bestiality. This word can be used to piss off fat people.
No fatties. I am not into obestiality.
by Frogs_and_Peas December 23, 2007
 
2.
The act of having sex with or wanting to have sex with fat people or a fat person.
Jeff:
Has Mike ever been with a skinny chick?

Dave:
Nah, he practices obestiality.
by lmxdurge February 13, 2011