My misfortune is overanalyzing, I'm told.
I doubt that your circle of academics spends a great deal of time involved in the arts and humanities side of the university. Attempt to sit in on a black studies or a women's studies class. Just to get the full impact, you need a day-hours class. Discover which of these professors habitually close their doors during class even though the hall is quiet. These are your target professors. Pick a freshman class. These contain the most impressionable students, and thus the most uninhibited professor. You should be aware that you will stand out in class and have marked effect on the content of the lecture.
Even better, go in drag as an 18 year old girl

(I can just imagine that)

or negotiate with one to record the closed-door lectures on your behalf in order to eliminate the perturbations your presence would cause.