Context: Driving a couple of high school boys to youth group talking about movies and the ones we want to see and the ones we are bummed we missed while they were in theaters.
Student: I really wanted to see Don Jon.
Me: That movie has an interesting premise. All that porn that you look at ultimately messed up your relationship with the woman you want to love. If you aren't careful you will get used to porn and prefer it to actual sex and then you and your relationship / marriage will be in trouble.
Student: I just think Scarlett Johansson is hot.
(Here is some further reading on how porn is changing sexual appetites from the NY Magazine. The Porn Myth.)