(Well, who DOESN'T do that?)
Likes to go into the library with one of those little restaurant-sized packets of mayo, go into the section on violent crime, smear a little of the mayo on his hand and a little on the crotch of his pants, wait until an older library patron is going by, then pop out with a big satisfied grin, and go, "Ahhhhhhh, SO gooooood... oh, HI THERE!"