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Koenma has two forms: teenage and toddler. Usually he remains in his toddler form, though occasionally when he leaves the Reikai (like during the Ankoku Bujutsukai) he will assume teenage form. He's the only son of Enma-Daiou, Emperor of the Reikai. If he had a mother, she was never mentioned (heh, I bet he's a test-tube baby). He has a little pacifier, and in that little paciifier is a lot of power. Koenma is egotistical and bossy (but if I was almost completely in charge of an entire world, I think I'd be a tad egotistical and bossy, too), and is kinda cruel to his two closest underlings, Botan and Saotome George. But Koenma does have a compassionate side (I'm sure), or else he wouldn't have given Kurama and Hiei such a light sentance (sure, Kurama did plan to give the Mirror back, but he was also indirectly responsible for the Mirror breaking).
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