The yakuza teacher idea is very original in the way they present it. There have been many 'odd' teachers, (GTO, Onegai Sensei, etc.) this one doesn't hope to attract people through being ecchi or anything. It's pretty much just extremely simple yet amusing humor. Most likely it was enjoyable to me because of the stupid things pretty much everyone does throughout the story. And how stupid the characters are. A truly humor driven anime. It's something nice to watch while surfing the web as you wait for everything to load, since you can pretty much tell when a hilarious moment comes up. The anime is not all fun and giggles though. There are some serious portions to the anime, concerning suicide and beatings.