Angry Monkey is not simply a sexual term, it is used to describe someone so angry that they can think of no other recourse than to fling their feces. Whether at the object of their anger or the walls of their cubicle the poo represents the anger. Often times the anger is dissipated by the act of poo slinging.
Some political anger junkie pundits are known for this in metaphor.
"That Beck can't get anyone to listen to him unless he gets all ANGRY MONKEY on the subject"
"Mr. Limburger has made a mess of this radio station with his ANGRY MONKEY ways"
"Don't go in the bathroom, Miss Clotter did an ANGRY MONKEY all over the walls"