It's probably just research for a sociological study of what arouses him.

After spending class almost as distracted by sexual fantasies as his students, a professor of Advanced Food Chemistry in the Netherlands decided to watch some porn at his desk. This would have been a great plan except that he apparently forgot the computer he was using was connected to a projector…and that the class was still streaming live online. It was a rare instance of online education actually offering more value than in-classroom learning. The professor was fired, although that probably had as much to do with the administration realizing Advanced Food Chemistry is kind of a joke as anything else. Scroll down for extremely NSFW image.

 

Sources: Redditor philana | Gawker