This 2002 film featuring Matthias Schweighöfer, Florian Stetter, and Jessica Schwarz, explores relationships of all types.
There is some interesting styling in the video for this film, which may make for an interesting discussion in a film art or film history unit or course.
There is some drug use, alcohol abuse, and talk of as well as implied sex. There is some nudity that becomes a focus of the scene and conversation just after 30 minutes in. There is an explicit sex scene 56 minutes in, and again at an hour and 22 minutes. Given the content and potential educational purpose, I would recommend this film at the university level only.