Cum juggling is when a person, with a mouth full of cum, deposits this cum into another person's mouth, and they pass it along in this manner either between themselves or more people.
This can also mean when a person takes ice cubes made of cum and actually juggles them, seeing how many passes can be done before they melt or they drop the cum cubes.
"Bro I was in a cum juggle that lasted for 12 people before that idiot swallowed the load."
Or
"Bro I was cum juggling for a solid 90 seconds last night. New record!"
A person(s) whos sole purpose in life is to chug cum;either from a bottle or directly from the penis; and juggle fuck; as in to cause shit(trouble). This person is often hated by a large amount of people.