Am not sure how to do this or even if I have done this myself without realising - so thought it needs a specific thread of its own for the experts to enlighten and educate us, in one easy to find, place!
Have googled up some pictures - the full medical name seems to be Sigmoid Colon?
Seems the Rectum is only 10-12cm long, so the penis doesnt necessarily have to be above average in length to be able to reach the Colon.
Found this cool website which gives a groovy 3D view of the female anatomy!
http://www.anatomyexpert.com/structure_ ... 426/40287/
Adding this picture too, because for some strange reason, it turns me on!
Some people have a sharp turn into the sigmoid, some a longer curve. On your diagrams the protrusions marked 'transversilis' are what I believe to be the valves. They have other names, such as rectal folds. See here: http://en.wikipedia.org/wiki/Transverse_folds_of_rectum
Again, not to put too much faith in anatomical models, the wiki links says about the folds:
They are usually three in number; sometimes a fourth is found, and occasionally only two are present.
I have occassionaly actually felt what I believe to be my wife's folds at the extreme reach of my finger while probing and lubricating her rectum. It feels like soft, delicate flaps which pinch off the end of the rectum. I do not know if that is two together or just the one that closes across.
Almost all anatomical drawings show the rectal valves The following video shows the valves in an open state, which they would generally never be in unless passing a stool or, in the case of anal sex, accepting a penis. However, you can learn to consciously control these valves with practice.
Leave it to porn to do a better job illustrating something. The following video shows a woman with a speculum in her ass. She is opening and closing her rectal valves, opening to her colon.
http://xhamster.com/movies/1700714/hotk ... _gape.html
As you might imagine by what you've seen in this video, the rectal valves can provide incredible stimulation of your cock and allow you to ejaculate beyond her valves and into her colon.
There are several positions that help shorten the rectum and align the colon to allow penetration. This is best achieved with her in either the spoons position with her knees drawn up against her chest, or in the doggy position, but with her pushed back, so that her knees touch her chest. These positions also serve to pull her cheeks apart, allowing even deeper penetration. As well, she can bear down somewhat to shorten the length of the rectum. This tends to be something a woman naturally does during an orgasm anyway. It seems to perfect, that at the time of her orgasm, she pushes her rectal valves down onto your cock and stimulates you to ejaculate in her colon.
I hope he won't mind me posting this, but Robert did an incredible job explaining the feeling:
Robert wrote:About the valves: We did that last night. It's something everyone should know about. OMG. I'll make a post on the forum when I get around to it. Simply put we took the advice about positions and did spoons and i helped her with her leg, pulling it back so that her cheeks were stretched apart. It was after around 10 min or something when I pushed hard against her bum that I felt something else against the head of my cock. Like a ring it stretched over and behind the head and I was then able to continue thrust a little back and forward and keep it there so that it sort of slid over and around the end of my shaft.
Here's another great example showing the valves working and demonstrating that a woman can take any size man in her ass.
http://xhamster.com/movies/2018952/xo_s ... ed=related
By the way, your partners rectal valves probably won't open this wide. The woman is this video has stretched hers using extreme sized items.
You mentioned you didn't know if you had ever done it without realizing it? You'd realize it. As someone else in the forum described, there is no better feeling than being balls deep in her ass, pumping your load into her colon while her rectal valves almost suck the cum out of your cock.
Let us know how it goes.
prettypink wrote:This is interesting to me because I do feel a change in the sensations when he goes deeper. I actually find it less stimulating than around the anus but often very calming and relaxing. Deeper penetration is something I need to work up to slowly, and a gentle and considerate lover whom I trust usually finds it easier.
Prettypink, that mirrors my experience with my wife.
She does not want me going too deep as she is trying to reach her orgasms.
After she is cummed out so to speak she likes me to pound away and then hold it up in her as deep as I can get it.
Lately I have really enjoyed holding it up there, wallowing in the delicious feeling of having the head of my dick in her 2nd sphincter as I shoot my load.