These two people show it. The girl is frustrated of course like most women but is playing a practical joke that gives her a substitute of the penetration pleasure (she does surprise epilation) and as she does the epilation (helping her in a way to compensate her absence of access to penetration of a man’s anus, as it “reduces the virility of the man” in another way) she takes the exact curvature that would be expected. Indeed the woman would sit on the man like that and her erect clitoris going down goes through the anus & reaches the prostate while she gets vaginally penetrated by the man’s erect pleasure.

The man’s pelvis could need to rise slightly on the anus side, for better pleasure.

This is how the most orgasmic sex can be had ! With the erect penis’s oblongular area (the underpart) meeting the erect clitoris all along and the testicles also stimulated by the clitoris. Our bodies are exactly made for that ! With enough flexibility the hands of the man can hold on the woman’s breasts through the process, as they penetrate each other. The most intense relation !