As far as I know, Roddick by DLarsen is the only free M3 character with genital morphs. Of course, it depends of the amount of detail you need, because Michaels default genitals are very limited. If you need something more realistic, try Satanicas or Insomniaworks'. See them at Renderotica; as nickedshield told, membership is required

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"Poser isn't a SOFTWARE... it's a RELIGION!"