when a penile is masturbated between two titties in an act of simulating intercourse, hence the "-bang."

When you eat dirt for the first time and leave your family to build a shack in the woods

When I male puts his wee wee in a female's dirty pillows.

To insert the penis between the breasts of a women. The women they can then add pleasure by using her hands to press/rub against her breasts (starting slow, and then adding speed) to release sperm from the man's penis. This is one of the best types of pleasure a man can receive.

The overwhelming echo you hear when a fat lady's titties bounce while walking.