Reciprocal Sight Of The Posteriors aka Reverse Cowgirl
The perfumed garden calls this one the "reciprocal sight of posteriors". I have also heard it called the "reverse cow girl position" because the woman is riding and she is facing away from her partner.
A book about sex therapy I read said that "This curiously impersonal method of intercourse allws each of the participants to fantasize about making love to someone other than their real partner."
I thought this was a little negative. If I wrote a book about sex therapy it would say something like "This position is favored by men worldwide who are making love to a partner with a great ass!"