a distorted but clever mis-read of "in the nookie jar" typically committed by non-native english speakers, lazy readers and people who get really excited by the word "nookie," but which has valid usage:
1. covert nookie
2. covert expression of nookie
3. a doubly emphatic expression of the same
4. the version of "caught with your hand in the nookie jar" that doesn't involve being caught
5. surprise nookie
"me and my boyfriend are taking a car trip...you know, a little nookie in the jar."
"i'm going to surprise her on her birthday: a little wine, some candles, and i've got a extra-special stash of nookie in the jar"