"Well, I could have gotten here sooner, but I stopped on my way to plow YOUR mother!"
In the anime
Cui is a rather cocky character who easily underestimates many of his enemies, but has a cowardly side when confronted by an opponent too strong for him.
In DragonBall Z Abridged, Cui acts similarly to his anime counterpart, but is shown to be much more rude and arrogant. He is also shown having no problem revealing to others that his species reproduce asexually (which disgusts Vegeta and later Zarbon when the latter is told by Dodoria).
Cui first approaches Vegeta after the Saiyan prince had just finished healing up his injuries from his battle back on Earth on Freeza Planet 218. He asks Vegeta where was he off to in a hurry and Vegeta replies that he's off to plow his mother. Cui then retorts that his species reproduce asexually, leaving Vegeta bluntly disgusted. Cui then grabs Vegeta by the shoulder and reveals to him that Freeza already know about the DragonBalls and how the Namekians made them and is already on Planet Namek searching for all seven of them. This surprises Vegeta as he wonders how does he know much, with Cui replying that the transmitter on the scouters was on the entire time on Earth. This leaves Vegeta puzzled as he claims to have turned his transmitter off, but remembers that Nappa came along with him to Earth and realizes that his idiot partner has never turned off his transmitter. Enraged, Vegeta takes a space pod and heads off to Planet Namek.
Cui eventually follows Vegeta to Planet Namek and confronts his arch-rival. After mocking the Saiyan prince about plowing his mother, Vegeta asks Cui what his power level was to refresh his memory. Cui then laughs and proudly announces his power level to he 18,000, which he thinks is the same as Vegeta's. Vegeta then brings up his Saiyan Official Handbook and reads a page regarding on how a Saiyan gets stronger everytime they are beaten near-death. This leaves Cui puzzled until Vegeta announces that he got destroyed on Earth by a low-level warrior, his half-breed son, a midget, and an obese man with a sword. Utterly surprised by this realization, Cui asks Vegeta why is he telling him all this information, knowing that he will never tell anyone this. Vegeta simply responds that he knows Cui will never tell anyone and makes his point clear by blowing him up in the air, killing him.
Cui: Hey there, Vegeta.
Vegeta: Speaking of simple, what is it, Cui?
Cui: Where are you off to in such a hurry?
Vegeta: Off to plow your mother!
Cui: Ha! Shows what you know, Vegeta. We reproduce asexually.
Vegeta: Gross, out of my way. -- "Episode 12: A Rose By Any Other Namek"
(Vegeta has just revealed to Cui about his defeat on Earth)
Cui: Why are you telling me this? You never tell anyone this!
Vegeta: Easy. Because I know you'll never tell anybody, Cui.
Cui: But-But I hate you! Why would I-- WAAAAAH! (gets blown up by Vegeta)
Vegeta: God, I love therapy. -- "Episode 13: Dr. Briefs Made This Episode In A Cave... WITHABOXOFSCRAPS!"