Similar to a beer bong, but the consumption of beer is rectally, using a funnel and tube to administer the beer as an enema. The primary purpose of butt chugging as opposed to drinking beer is that alcohol administered as an enema has 3x the effect of alcohol taken orally.
We dared my friend to butt chug his beer and when he did he got totally wasted!
The act of introducing any liquid or fluid by way of the rectum. An alternative to the more common way of oral intake in which any effects of the matter, usually alcohol, that has been reversely passed through the sphincter, is most likely to be felt much sooner an up to 3 times its usual potency.
Johnny was able to pass the police check point due to a last minute decision to buttchug his drinks for the evening thus leaving his breath smelling sweet and sober.