Depending on the kind of life you've led, the phrase "beer bong" can be loaded. For some, it may conjure up memories of puking on your ex in West Palm Beach. For others, you may not even know what the hell it is.
If you've ever watched somebody's Instagram story and seen them drinking from a tube which is attached to a funnel, you are looking at both an absolute maniac and a beer bong. You should DM them and shoot your shot.
Drinking a beer bong is different from drinking something the normal way, because the drinker is not in control of the amount of liquid entering their body, nor the speed. Gravity is in charge. Most beer bongs have a valve which engages/disengages the flow of liquid.
Beer bongs can also be inserted rectally and used to administer an alcohol enema, frequently called "butt chugging" or "boofing." Do not do this.