to do the nasty, i.e. to have sex. taken from Russle Hoban's novel Riddley Walker.
"Every body knows Aunty. Stoan boans and iron tits and teef be twean her legs plus she has a iron willy for the ladys it gets red hot. When your time comes you have to do the juicy with her like it or not. She rides a girt big rat with red eyes it can see in the dark and it can smel whos ready for Aunty. Even if they dont know it ther selfs the rat can smel if theyre ready."