[[Sex]] where the person with a [[penis]] penetrates their partner [[testicles|balls]] deep - all the way to the base (sometimes called "hilting"), with the entire member inside the vagina or anus and only the [[testicles]] visible. [[Cross-section]] or [[x-ray]] shots often show the penis resting against the [[cervix]], if not outright [[cervical penetration]].

h4. See also

* [[cervical penetration]]
* [[cum in pussy]]
* [[internal cumshot]]
子宮をノック