When you and your partner are engaging in anal sex doggystyle position and you're about to ejaculate, you kick your legs clear off the bed with the soles of your feet parallel to the ceiling and balance your weight on your partners back to a completed rectal endo or anal endo.
After watching reruns of doogie howser MD I gave my partner an acute rectal endo.
The 'Rectal Endo' is the medical term used to describe this sexual right of passage and the 'Anal Endo' is the more commonly used street slang.
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