This is my favourite, and the one we use. Another one I like though, is “frolicking”
Is it Thursday already?
My SO says there are only three stages of life: hungry, horny, and tired. So we can discuss how we are feeling in front of others by saying things like " I am deep in stage 2 right now". “Can we take care of stage 2 this evening?” Want to have a stage 2 lunch?" If we don’t have to speak in code, then it is “I want it”.
If my wife asks me if I want to get punished, I know a blowjob is in the works (old joke, so old I forget the origins, but I am too busy racing up the stairs to worry about it when it is said)
We also say, “let’s go spelunking”, or “take a nap” or let’s “go change.” is it obvious that our kids are always around or what 
Snack.
Fighting Crime.
Sometimes it’s brought up by saying “You notice a lot of crime in the neighborhood lately?”
“Yeah someone should really do something about it”
Spelunking, ditto
Schtuuping (what? Didn’t you have a german grandmother?) Also, when playing Civilization II, when you attack a city the sound effect sounds exactly like “schtuup schtuup schtuup”. Seems rather appropriate.
But mostly, gettin’ frisky. Yeppers, when Mr Wiggly starts getting frisky, DO NOT expect me to answer the phone!
We call it “OINGABOINGA” after a scene from the movie “Krippendorf’s Tribe” where the Prof.Krippendorf char gets drunk with the Jenna Elfman char and they get all tribal and start having wild monkey sex in body paint in a simulated grass hut.
IDBB
“turning the cross around”
My Catholic ex-gf always wore a cross on a necklace and, in certain positions, it would wind up between our lips when we kissed, which was kind of a mood killer. So she’d turn her necklace around so the cross was on her back. Hence, serious snugglebunny sessions became “turning the cross around.”
We make sex, too. Sometimes we “have love”. Other times we “copple”.
we just call it Grrr. it started out with one of us going ‘grrr…’.when in the mood…but now, we will quite often just say- ‘wanna grrr?’
we leave out all of the snarling, biting and clawing, and whimpering sounds for the sake of time and decency.
When we were dating and passionately in love: She called it Horseback Riding (which was a big boost to my ego)
On Our Honeymoon: We called it “Matressizing”
After the birth of our 1st: “Let’s go make Jessie a brother”
After the birth of our second: “A Calgon Moment”
While we were seperated: “Grabbing some fast food”
Just Before our Divorce: “Masturbating”…cuz that’s all there was
I used “not sleeping together” or one of many variations. “Do you want to not take a nap.” “I don’t think I need a little sleep.” The great thing is that when said quickly you can use it in polite conversation and no one will notice.
I just started a new relationship, so for us now breathing works just fine as an invitation.
we’re boring. just the good, old-fashioned “wanna fuck?” works for us. I can’t believe I used my 700th post for this.
We use the cake variations too…
“Let’s go on a bombing run…”
In the vein of mixed euphemisms, we sometimes “make sex” or “have love”, and when we are feeling more formal they translate to “making the sex” and “having the love”. Tongue-in-cheek romantic version is “making sweet, sweet love”.
For those struggling to create their own euphemisms, try this site:
[URL=http://walkingdead.net/perl/euphemism]
80% of the time, it’s “wanna do it?”
Hm. Not much of a euphemism?
Otherwise, it’s referred to as “Watching the Jeffersons”, which
is from my high school years:
2 couples were on a boat; my guy and I were in the back cabin below deck, watching the little portable TV. Friend (whose parents owned the boat) asked me the next morning what happened.
Since I chickened out and my vitrue remained intact, I told her the truth: We fooled around a bit, and then watched the Jeffersons
Taking a nap, or playing Yahtze. A couple of years ago we were trying out several different board games, and one was yahtze. I hated the game, thought it was stupid and boring. But later that night, we were playing around, and just as the moment was reached, my SO yelled out YAHTZE! I started laughing so hard I nearly hurt something.
My wife and I call it many different things, but it’s usually pretty direct, like:
Her: “Wanna stick it in me?”
Me: “Ok”
Mostly, I “do” her or “stick it in” her.