Based off memory. Also, spoilers. (Mature language)
The class is taken to a resort sort of place. It has a beach, it's got a nice looking hotel/inn- it's an all around beautiful place to be. But of course, there's some sort of a monster to be dealt with. Even more, that monster turns out to be a perv. Using weird illusions, it makes it look like the girls and guys are naked when they really aren't. Well, until Mr. Main Character ends up legitametly naked.
Animation was alright.
Sound was alright.
Characters were the same as in the TV series.