They are talking about the phoenomon of "apports", the production of objects by ghosts, and the professor seems quite agitated, and says "disassociate". The translation goes "I'm so bad and mean", but its dictionary meaning is "to disconnect yourself from something"
What did he mean by "disassociate"?
professor- I know you're talking about apports! Why are you yelling?!
Mel- I'm not yelling.
professor- I'm yelling, right?! I make that mistake.I'm sorry I tend to disassociate.
Mel-That's an understatement.
professor - Wh-what do you want?