Can also be used in place of "see you later".
Taken from the noise your mouth makes when you make fish mouth movements.
Bopbop is an onomatopoeic word.
-"Ciao Daniel. Bopbop x"
-"Can I give you a blow job later?"
-"Yea come round."
-"OK. Bopbop x"
Can be used the same way as Get 'er Done.