A visible protrusion of the stomach caused when something (usually a [[penis]], [[tentacles]], etc.) pushes against the stomach from the inside.  Like [[cervical penetration]], it is impossible to occur in reality without fatal damage.

If the bulging of the stomach is caused by the stomach filling up with something (usually a fluid), it is called [[inflation]].

h4. See also

* [[large insertion]]
* [[full stomach]]
* [[deep penetration]]
* [[intestines filled]]
ボコォ 腹ボコ