The Machine

It starts in a slow, deliberate pace.
In. Out. In. Out.
Slowly, but surely, it picks up speed.
A powerful thrust and withdraw into a tight space that seems made for it.
Hot heat builds as the two continue to build their friction faster and faster.
Lubrication is added to keep them from hurting each other, but the heat still builds.
They reach levels of such force and speed that it seems that one of them will break.
Harder. Faster. In. Out. Harder! Faster! In! Out!
Man and woman or the pumping of a mechanized piston, it matters not.
Both reach a primal level of determination that sometimes can not ever be sated.