Pencil Masturbation 

When your mechanical pencil is out of led, so you repeatedly and forcefully push the eraser to make sure that you don't have any extra led in there. The sound it makes is like fapping. When led comes out, it is called pencil ejaculation.

Dude, that guy in class kept performing pencil masturbation. Like, get a new pencil already!

Pencil Masturbation by Liberty5000 February 20, 2019