No matter what some guys will tell you, being fucked (taking your sexual partner's erect cock/dick/penis) inside your ass (buttocks) is decidedly not the most painful experience anyone will ever have to endure. Yes, it does require some getting used to, but the gratification out-weighs whatever initial discomfort any man feels, unless his partner's cock/dick/penis is simply just too large to insert. And that occurrence is just somewhat a myth and the sphincter muscle is very flexible and can generally adapt to any size of manhood (cock/dick/penis).
Doggy-Style is the typical bottom position for most men and is shown in the image above. In this picture, the bottom (the one being fucked) is, naturally, on the bottom with his back against his top's (the man doing the fucking) chest. Notice the downward dip on the bottom's lower back. This is further illustrated in the chart below:
The correct use of this posture while being fucked (penetrated) doggy-style maximizes the amount of pleasure the bottom feels as his top's erection massages his prostate. This pleasure is the very reason so many men prefer to be fucked in the ass as opposed to fucking another man in his ass. It is indescribable ecstasy! Trust me, I know this for a fact as I am an exclusive bottom-man!
If my prostate isn't properly massaged by my top's enlarged and erect cock/dick/penis, then I feel no pleasure from being fucked! There is no sexual pleasure or satisfaction for me. I may as well be on my elbows and knees for nothing. The sex is like having someone inserting a cucumber in and out of my anal opening.
Above is the correct position for the bottom to assume as he prepares for his top to insert his manhood inside his ass (buttocks). To guarantee pleasure, commit this position to memory and recall frequently. Remember, while being fucked, if you lose the pleasure sensation, adjust your position accordingly.
In the passion of the sexual act, it is easy to forget the proper posture. Make sure you are able to maneuver both you and your top back into place. Enjoy your tryst (encounter)!
Take care and stay proud and bare!