Anal Sex: A 17th-Century How-To Guide

I declared that I would translate a chunk of Bian er chai that describes the mechanics of sodomy in the first post (see below), so I guess I should apologize for holding off so long on it.
[ETA, 19 days later] So I guess I wasn't done being busy. But NOW I AM, so here is the sodomy! Again from the Ming collection by Master Moon-Heart (see below again), more specifically my favorite of the 4 sections, "Chaste Love."

After cleverly weaseling his way into the school at which the lovely but virtuously chaste Zhao Wangsun is studying and falling conveniently ill in order to get the friendly Zhao to join him in his sickbed, the Hanlin scholar Feng Xiang gets his dubious way with the hapless Zhao. After they begin meeting every night, Zhao asks:

"Brother, you say that there's pleasure to be had in doing this, but why is it that I only feel the harshness in it?"
The Hanlin replied, "With you, brother, I'm only going slowly, as if I were water grinding jade. So I only get to enlighten you a little, then must sound the retreat and rest my troops. You've never actually been in the heavenly planes yet."
Zhao said, "There's really a 'heavenly plane' in this?"
Explained the Hanlin, "That place has seven inches that is free of feces. Above these seven inches, there is an orifice, which opens when something enters, or when you are using the bathroom. Otherwise it stays tightly shut. When we're at it, the 'grain tunnel' should be shut tight so that the upper orifice is closed to keep out the filth. In those seven inches, there's also a 'lustful orifice.' After thrusting at it for a thousand times or more, it'll start itching, and the lustful orifice will open by itself, releasing licentious fluids. It's better than words can say. If it hurts, then it must be an amateur doing it. The back door's actually pretty roomy, if you want to see the fun of it, you must go at it a while for the pleasures to start."
Zhao replied, "If that's the case, I must confess my ignorance. I'd like a demonstration, though."*

Whereupon the two lock out the servants and go to it.

For the really curious, everyone in BeC uses spittle for lubricant, and often sodomy is compared to vaginal sex. The phrases "as when a woman tends her husband" or "as if with a woman" come up a-plenty here. There're also a bevy of interesting positions: cowboy, doggy-style, missionary, spoons, etc. And since I heard someone ask the question once, yes, there was kissing, fellatio, and other non-anal activities going on, too. Anal intercourse does seem fairly central, though, particularly in "Chaste Love." (Most of the earlier bottoms were the Hanlin's various servant-boys, and one of Zhao Wangsun's, too.)

But really. A thousand or more thrusts? Are these people 17th-century, nanfeng**-following versions of the Energizer bunny or what?


*My translations are to convey flavor, not necessarily linguistic fidelity, of course. But I gotta say, this is probably the best come-on line ever.
**The pun turns on one of those zillion Chinese homophones. Nanfeng= "Southern Wind (Taste)"/"Male Wind (Taste)"