Well, strong booze will be absorbed faster if poured in the nether regions. The mucus membranes are really good at that, however, it can be life threatening because it's very difficult to control the dosage of alcohol being absorbed. I doubt beer would be very dangerous, though. It would likely just be reallly uncomfortable. Imagine poring something with refrigerator temperature into a cavity with body temperature. In real life it would likely induce a sharp scream followed by a swift kick in the balls.
It's hot in a comic, though.
I didn't really like this one. I mean sure the girlfriend seemed to be okay with it (which is questionable seeing as how we don't know what was going through her mind as this was happening), but the guy basically just raped the other girl.
Oh...A netorase tag? Interesting. Also the one that let the netorase happen was actually his girlfriend? I must admit, I went in kind of expecting what I think most would expect from that tag with the guy letting his girlfriend be with another dude, but I was pleasantly surprised. Also the combination of alcohol + pretending to be asleep...Quite the deadly hentai combination.
It's hot in a comic, though.