"Surely, Madam, a friendship between the two sexes may subsist, and be supported without---Fy! Mr. Shandy:--Without any thing, Madam, but that tender and delicious sentiment which ever mixes in friendship, where there is a difference of sex" (1.18.12)
Sure, men and women can be friends—they can share a "tender and delicious sentiment" that seems even more attractive than sex, at least as it's represented in the novel. Notice that it's the woman, Tristram's imaginary companion, who expects him to say something dirty.
How do the slight touches of the chisel, the pencil, the pen, the fiddle-stick, et cetera,—give the true swell, which gives the true pleasure! (2.6.7)
It's hard to keep our minds out of the gutter when Tristram is writing lines that combine "slight touch" with "swell" and "pleasure." Tristram links writing (or any kind of art) to sex and says that both acts give the same kind of pleasure. Um, okay, Tristram.
"My total ignorance of the sex … has given me just cause to say, That I neither know, nor do pretend to know, anything about 'em, or their concerns either" (2.7.3)
Toby's lack of interest in sex means that he has no interest in women, either. Women seem to be important only for sex in Tristram Shandy. They're rarely mentioned in any other context except when they're giving birth, sneaking around, or, in Mrs. Shandy's case, sitting at home knitting a pair of breeches, which, let's face it, are kind of a sexy piece of clothing.
My brother does it, quoth my uncle Toby, out of principle.—In a family way, I suppose, quoth Dr. Slop.—Pshaw!—said my father,—'tis not worth talking of.
For Walter, sex is about procreation—it's a family duty that he does systematically and according to a rigid schedule. You have to wonder if he was always this way, or if his nasty attitude killed his ability to enjoy love-making.
He would shake her by the hand, or ask her lovingly how she did,—or would give her a ribban,—and now and
then, though never but when it could be done with decorum, would give Bridget a—
Just what is Trim giving Bridget with decorum? We'll never know, because, like most of the mentions of sex, Tristram cuts us off right at the good part. We're left to imagine the worst (or the best), even though Tristram continually tells us to keep our minds clean. We're sure he's a perfect saint.
Can you tell me, Gastripheres, what is best to take out the fire? (4.28.1)
Before penicillin, a bout of syphilis, a very common STD back in the day, could be really nasty. When a hot chestnut lands on the scholar Phutatorius's lap, it makes his crotch burn with fire: in other words, he's got the pox. These high-falutin' scholars are whoring around with everyone else, and Tristram gets to make an extended dirty joke about it.
It had ever been the custom of the family, and by length of time was almost become a matter of common right, that the eldest son of it should have free ingress, egress, and regress into foreign parts before marriage,—not only for the sake of bettering his own private parts, by the benefit of exercise and change of so much air—but simply for the mere delectation of his fancy (4.31.7)
One of the only people who seems to enjoy sex ("the mere delectation of his fancy") in Tristram Shandy is Bobby, Tristram's older brother who lives and dies offstage. The association between 'foreign parts' and fun sexy times shows up again, when Tristram remembers having a good time with a peasant named Nanette in the south of France.
What signifies it, brother Shandy, replied my uncle Toby, which of the two it is, provided it will but make a man marry, and love his wife, and get a few children.
Like Walter, Toby thinks sex is for procreation. Ever the romantic, he also acknowledges that love has something to do with it. Of course, it's all abstract for Toby, who's never gotten close enough to a woman to test out his theories. One word, Toby: deodorant.
The more she rubbed, and the longer strokes she took—the more the fire kindled in my veins—till at length, by two or three strokes longer—than the rest—my passion rose to the highest pitch—I seized her hand—
Welcome to one of the book's the most explicit passages. Trim is telling Toby how a young nun used to rub his leg, but, well, it seems a lot like she's rubbing something else. Notice, though, that Trim doesn't get to finish. Like every other sex act, it's coitus (or something) interruptus.
Mrs. Wadman naturally looked down, upon a slit she had been darning up in her apron, in expectation every moment, that my uncle Toby would go on. (9.25.7)
Tristram never misses a chance for a dirty joke. A "slit" in her apron? You might as well just call it a vagina and be done with it.