Scrot = Naughty-bit pervert (from a Joseph Wambaugh novel) Mope = One who exposes himself to a blind person. Often used with "Felonious Mopery" Squint = Half a squirt. Similar to "Roach" in that both are adverse to light, but squints are slower.
Cops have other endearing names for members of society:
Goblin Solid waste Blotto Slamhog/Slamdog Carl Neck Mook FLASH (Fat, Lazy Ass, Shit Head) Bug
and more. Most are department-specific.