R. Dorothy Waynewright is an extremely advanced android, and a central character in the anime,"Big O". But she is far from being devoid of personality or having hobbies. She was created by Tim Waynewright who lost his daughter forty years ago, and created R. Dorothy in her memory. R. Dorothy herself often speaks in a monotone, can be moody, has a dry sense of humor and sarcasm, enjoys music and piano, has a soft spot for entities like her, and often banters with Roger Smith.

She has short brown hair in a pageboy cut, and fathomless black eyes. Her skin is also very pale, giving her something of a ghostly appearance, at first. She is frequently seen wearing the trademark black garb of Roger Smith's household, in this case, a dress. R. Dorothy also wears a pink headband that doubles as a CD drive. Her face and body shape are very lithe and slender, looking very refined. However, she is not one to underestimate! She possesses balance and strength above the normal human, and her frame to be made out of a heavy metal alloy.

R. Dorothy also shows some feelings toward Roger Smith, although not always clearly evident. She buys him a gift for Heaven's Day (suspiciously like Christmas Day ...) in the form of a black tie, and is upset when he proclaims that he doesn't like to exchange gifts. She shows an interest in playing piano, and often deliberately plays badly to wake Roger up when he is sleeping late. She also rescues a kitten named "Pero", and took it home, even dressing it in a small black suit so Roger would not disapprove. (His rule was that everyone living there wore black.) Toward the end of the series, Dorothy asks Roger a flustering question: "If... neither of us had any memories, and we met... so, then would you and I fall in love as well?" It was left unanswered.