Brother and Sister. Twins. I think they run some sort of circus or amusement park. Kankan is the guy while Ranran is the girl. They seem to have an obsession with pandas. Like that giant panda (Ranma Satome's father anyone?) Chacha had to fight.
In their first appearance, Ranran and Kankan turn Chacha and her friends into babies! Even Seravi and Dorothy changed and that is how we first find out that Elizabeth is modelled after Young Dorothy. The second time the appeared, they turned Chacha, Riiya, Shiine, Yakko, Suzu and Marin into animals. Marin said "You turned me into a duck instead of a swan!" My friend heard Yakko comment that she remembered the place that Ranran and Kankan were running, almost backing up the story I heard saying she was a monkey (What animal performs in circus? Monkeys of course) But Yakko was turned into a wart hog.
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