I first read excerpts from Geoffrey Chaucer's The Canterbury Tales during my junior year of high school. (Brief synopsis: a bunch of pilgrims are traveling together and decide to tell one another stories.) We read a modern English translation, and I was bored out of my mind. Years later in graduate school I read all of the tales in their original Middle English and, thanks to some excellent footnotes, was able to appreciate how over-the-top sexual the tales actually were.
OK, let me be upfront with something right off the bat: that title is an exaggeration. As opposed to 50 Shades, you are unlikely to come across butt plugs, Keggle balls, or sex dungeons in Chaucer's best-known work. However, that doesn't mean that these tales aren't graphic and bawdy enough to make even the most hardcore Christian Grey fan blush.
For some reason, a lot of us (or, OK, maybe just me) assume that dirty jokes didn't exist before twentieth century. Whenever I read older works, I'm shocked to find how many different euphemisms there are for words like "vagina" and "syphilis". And boy does Chaucer have a lot of references to vaginas.
If you've never read a graphic sex scene in Middle English before than are you in for a real treat. I would suggest reading the following passages out loud. Not only does it make them easier to understand (even if you've never read Middle English before, you'll probably recognize a lot of the words when you hear them), but you'll also gift anyone within earshot with some beautiful passages of couples fornicating in trees and sticking their butts in each other's faces.
1"Now sire and eft sire, so bifel the cas/ That on a day this hende Nicholas/ Fil with this yonge wyfe to rage and pleye/ Whil that hir housbonde was at Oseneye,/ As clerkes been ful subtile and ful queynte,/ And prively he caught hire by the queynte/ And sayde, "Ywis, but if ich have my wille/ For deerne love of thee, lemman, I spille,"/ And heeld hire harde by the haunche bones/ And seyde, "Lemman, love me al at ones/ Or I wold dyen, also God save me!"
— "The Miller's Tale"
Basically, a young wife is fooling around with a man named Nicholas while her husband is away (the scandal!). But here's the real naughty bit. Know what queynte is? Try sounding it out. Yup, that's a word for vagina. He caught her secretly by the queynte indeed. Also, "haunche bones" means thighs, btw.
2"This Absolon gan wype his mouth ful drie./ Dirk was the nyght as pich or as the cole,/ And at the wyndow out she pitte hir hole./ And Absolon hym fil no bet ne wers,/ But with his mouth he kiste hir naked ers/ Ful savourly er he was war of this./ Abak he stirte and thoughte it was amys,/ For wel he wiste a woman hath no berd./ He felte a thyng al rough and longe yherd/ And seyde, "Fy! Allas! What have I do?"/ "Tehee," quod she and clapte the wyndow to."
— "The Miller's Tale"
Some backstory before we get to the good part. Absolon is the unwanted suitor of Alison (she's the miller's wife who's having an affair with Nicholas in the first quote). Absolon wants Alison to give him a kiss. Instead, Alison sticks her butt out the window and Absolon accidentally makes out with it. The fact that he only realizes his mistake when he feels her pubic hair makes this even better.
3"I wolde no lenger in the bed abyde/ If that I felte his arm over my syde/ Til he had maad his raunsoun unto me./ Thanne wolde I suffre hym do his nycetee./ And therefore every man this tale I telle:/ Wynne whoso may, for al is for to selle./ With empty hand man may none haukes lure,/ For wynnyng wolde I al his lust endure/ And make me a feyned appetit./ And yet in bacon hadde I nevere delit."
— "The Wife of Bath's Prologue"
Let's break this down: the Wife of Bath goes through an insanely long prologue before she gets to her tale, basically talking about her husbands and her sexual adventures. In this, she talks about how she'll only put up with this guy's advances if he gives her money first, and then she only pretends to enjoy the sex. Here's the real kicker: when she says, "And yet in bacon hadde I nevere delit," "bacon," my handy Chaucer footnotes tell me, is of course "old meat preserved by salting." Yeah, she's calling his dick old meat and saying she doesn't like it. Brutal.
4"As help me God, whan that I saugh hym go/ After the beere, me thoughte he hadde a paire/ Of legges and of feet so clene and faire,/ That al myn herte I yaf unto his hoold./ He was, I trowe, a twenty wynter oold./ And I was fourty, if I shal seye sooth./ And yet I hadde alwey a coltes tooth./ Gat-tothed I was, and that bicam me weel./ I hadde the presente of Seinte Venus seel./ As help me God, I was a lusty oon/ And faire and riche and yong and wel bigon./ And trewely, as myne housbondes tolde me,/ I hadde the best "quonyam" myghte be."
— "The Wife of Bath's Prologue"
Wife of Bath, you cougar. Here, she talks about having an eye for a much younger man (because apparently she always likes them young, see "old meat" above). Luckily, she doesn't think the 20 year age difference will matter, because she has the best "quonyam" (another new world for vagina) around. I like her confidence.
5"He stoupeth doun, and on his bak she stood/ And caughte hire by a twiste. And up she gooth./ Ladyes, I prey yow that ye be nat wroth./ I kan nat glose. I am a rude man./ And sodeynly anon this Damyan/ Gan pullen up the smok, and in he throng."
— "The Merchant's Tale"
So in this tale, an old man named January (who's kind of a jerk tbh) marries a much younger woman named May, who promptly begins having an affair with a young man named Damyan. January becomes blind, and doesn't realize this is going on. In this scene, Damyan is waiting for May in a tree. May tells January she wants to get some fruit from this tree and climbs on his back to get a boost up to the waiting Damyan, who grabs her and immediately starts having sex with her. Like, she's barely off her husband's back and they're going at it. In. A. Tree.
6"This faire wyf acorded with Daun John,/ That for thise hundred frankes he sholde al nyght/ Have hire in hise armes bolt upright./ And this acord parfourned was in dede./ In myrthe al nyght a bisy lyf they lede/ Til it was day, that Daun John wente his way/ And bad the meynee, "Farewell! Have a good day!"
— "The Shipman's Tale"
A merchant's wife can't pay her debts and doesn't want her husband to know, so she turns to the world's oldest profession for help. She offers to sleep with a friend of her husband, who happens to be a monk, in exchange for the cash she needs. The monk is only too happy to oblige, keeping her in his arms "bolt upright" (that means on her back) all night.
7"But faire and wel she creepe into the clerk/ And lith ful stille and wolde han caught a sleepe./ Withinne a while this John the clerk up leepe,/ And on this goode wyf he leith on soore./ So myrie a fit hadde she nat ful yoore./ He priketh harde and soore as he were mad."
— "The Reeve's Tale"
A young student vows to get revenge on a miller who stole from him by tricking his wife into sleeping with him. (Basically, he tricks the miller's wife into thinking she's getting in bed with her husband, but really she gets in bed with him.) It's a gross and inappropriate and frankly rape-y trick, but Chaucer isn't concerned with that and the miller's wife enjoys herself, noting that she hadn't had such a good night of sex in years. Apparently the student "priketh" pretty good.