In one of his earlier versions, I'd read that he was working with some of those people who was born without the pelvis or legs. I have no idea how this one works.
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Having watched it again in high quality and pause.
1) Look at the woman's left ankle area under the skirt. There is no tattoo there.
2) After the change, look at the man's left ankle area under the skirt. There is a tattoo there now.
It's obvious that the man did not really get the woman's lower half because the woman's left ankle didn't have a tattoo at the beginning of the video. There must have been some camera sleight of hand.
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Having watch it a 3rd time, it's all camera trickery.
The 1/2 woman and the full woman are not the same. She is one of those woman who was born without the pelvis or legs. The 1/2 man and the full man are not the same person either.
Solved.
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Someone on Youtube also mentioned the shadows. When he starts, the shadows are about 1pm, later in the same video, about 4pm. Everyone is in on it, they are all actors.