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1.
A male on male sexual activity that occurs when neither partner is too tired or too straight.
Only one day into what seemed an innocuous road trip between friends, Cole and Derek suddenly came to the realization that their relationship could no longer be bearably platonic, and they engaged in the sexual abandon and high art of butt bonding.
by Detective Kernel January 23, 2011
 
2.
what you get when you don't fart for an uncomfortably long time and then you leak a real flabby one.
tanner unleashed his daily buttbonding and proceeded to be showered with farthate from everybody in the zumba class.
by isochronismisms! May 30, 2009