The theory says it is to get rid of the residual semen that were left behind the competitors and inject our fresh seeds. Since most of the plugs fit into the sockets without gap (according to statistics, men agree, women disagree), I think what the scholars are trying to describe is this scenario (courtesy of Growforce).
I do not see ANY of the residual fluid pushed out. If I happen to be in the ideal scenario visualized by the scholars, I will be among the many guys waiting for out turn (which looks like a…), but despite the theory, I am just helping the guy that went in there before secure his seed. First in, first served.
I guess the logical behavior to really secure the seed is to follow these steps:
- Let the female partner stand straight up, possibly with her legs wide open to loosen up her pelvis
- Shake her torso hard to let all the "leftover" come out of her body
- Connect the plug/socket together and complete the installation
- Make her stand again but upside down, and shake her torso to ensure the semen slow into her body.
People who follow the above procedures might exist, in a secret underground club. I am starting to feel that whoever is right, the ideal environment for procreation has been realized by our sex industry.