Prison school obviously has a fanservice/humor goal and it blasts it out of the park.
PS is a masterpiece of the ecchi genre rivaling DXD, to be sure.
Long reviews waste your time, so here's a short sweet paragraph.
The art in PS is of the highest caliber. All lighting, shading, expressions, and details are drawn insanely well. This anime had me bursting out with laughter more so than any comedy I have ever seen. Try not to eat or drink liquids when you watch this because every couple of seconds you're bound to spit it out. This anime is LOADED with AMAZING fanservice and everything is incredibly detailed. The plot is also unique and absolutely perfect for setting up the humor and fanservice of this series. Sure, you won't find yourself in tears like a good drama plot but this anime is not a drama. It's downright hilarious and it crosses so many lines. The soundtrack is perfect for the series as well. There's lots of epic tunes to make a huge deal out of something so hilariously simple. The cast of characters is also brilliant. At first I thought you these guys were so weird but they actually turn out to have very specific personalities. The female leads are also very individual and the epidomy of sexy. All in all, if you love ecchi, fanservice, and comedy then this is your masterpiece rivaling ecchi tyrants such as DXD.
-Oustanding animation and detail.
-Excellent non-cliche characters.
-10/10 fanservice around the clock.