Due to the show's shortened 15-minute length, the basic plot of Hen Zemi is introduced to the viewer relatively quickly. See, there's this special course being offered at the local college that specializes in disturbing traits of the truly perverted. Even though university student Nanako Matsutaka is relatively normal and free of any real perversions, she ends up taking the course to be closer to her crush Komugi, only to discover that there are some real freaks of nature in college.
We can go through examples, but you might want to hold onto your lunch. While some students specialize in the biology of fruit flies (raised in their own ear canal), others opt for a psychological approach, such as determining where the border between touching fingers and touching boobies exists. Komugi? Well, he would rather study the effects of secretly urinating into a diaper while doing menial chores, but Nanako...only seems to be drawn closer.
While the plot does depend heavily on sexual deviancy and test the limits of taste in animation (perhaps part of some grander experiment in social psychology?), it is a unique approach, nonetheless. You just might have to do it on an empty stomach.
Dependent more on content rather than glamour, the animation for Hen Zemi is unspectacular. Backgrounds are drab in order to bring attention to the characters, and the settings themselves don't stray far from the college atmosphere. The character designs themselves border closer towards realistic, as no one is drawn as a rail-thin beauty or an Adonis model, but they are still dressed like mannequins, forced into embarrassing outfits. In retrospect, this show could have benefitted more as a radio comedy.
Any show about the perverted is going to require some colorful characters. While straight-laced Nanako is just there to meekly squirm away her embarrassments, the other classmates are a study on bizarre behavior, despite their plain exteriors. It's great to watch Mizukoshi pant from her own fetishes, while Komugi grins passively, quite excited to have people steal away his girlfriends. All of this is done by the watchful eye of Dr. Meshiya, a twisted soul of a professor who looks like a mix between Kinpachi-sensei and a piranha.
Once again, the minimalism for the music goes without saying, but my guess is a Casio keyboard was used for about half of the show's soundtrack. The opening and ending themes are pretty much unnecessary for the show's content, and the acting isn't all that memorable either. All the actors need to do is read their lines and sit back as the audience makes sick faces.
For one thing, this is a Xebec production (Rio Rainbow Gate!, To Love-Ru), the studio known for their sexually-titillating shows, so you're not going to get an Oscar-nominated performance, but their infamy alone should draw some people into the seats. However, you do get some name recognition from the show's director Takao Kato, who has directed both of the aforementioned Xebec shows. The biggest hit the show might take, however, is that it really wasn't advertised as a half-episode. For all the little hype the show had going for it, it loses a lot of its impact by quitting halfway.
The gulf between setup and punchline in comedy can sometimes be as wide as the Grand Canyon. Take, for instance, the main joke from the documentary The Aristocrats—the intent is to make people laugh and for the punchline to hit the funny bone with pinpoint accuracy, but sitting through the raunchy joke in the middle may test one's mettle. Hen Zemi works in the same way, attempting to squeeze a laugh out of of the audience while grossing them out with implied fart humor and sexual fetishes.
Strictly speaking, Hen Zemi could end up being the 2 Girls 1 Cup of anime—it sounds funny on paper, but you just might end up leaving halfway through the performance.