shaking penis

post #4024040 post #4508806 post #3676743

^{note: examples above are animated}

Usually involves a character using their hands to shake the penis, but can also describe a character "wagging" their penis in a slight side-to-side motion by moving their hips, similar to the wagging motion of a tail.

Not to be confused with...

bouncing penis — a penis moving up and down, caused by the movement of the character's body (e.g. jumping, walking, being thrust into)
flexing penis — a sudden jumping motion of the penis caused by flexing of the pelvic floor muscles
throbbing penis — the penis trembling or pulsating involuntarily, usually caused by blood flowing into the penis during an erection, or contractions during ejaculation