Why did both costumes look the same?

Michael did not know what it was about this magic fancy dress costume which was supposed to turn him into a muscle bound man that had turned the costume into that of a sexy cat & him into a horny sex crazed woman.

It was only when his girlfriend got home and saw what had happened to him that he worked out he had put on her costume by mistake.

So she slipped on his and turned into an extremely horny well-endowed man so she could show him the finer points of being a horny woman.

Are you sure it's going to fit in?