This was actually South Park's interpretation of the Orko character from He-Man. In the episode trilogy of Imaginationland, this character appears with a "D" on his shirt instead of the "O" that was original to the He-Man series.
My friend has 2 red eared sliders and they have red ears so that is why they are red eared slider and if there ear is orange they might just be young or been in the water it went away but mostly it...