@dlepah: Yes, he said the full color made it take a "staggering amount of time". Also went back to the normal lips because he had negative feedback about them. (I agree, they looked stupid)
Summary: MC wakes up in the older aunt's body. Later finds out that his aunt went back to Tokyo in his body and the father knew it was her. Also: The younger aunt isn't actually his real aunt either, she was a boy that swapped with her. They don't say if the boy was also a relative or a stranger tho, etc. Part 5 is supposed to be the end of the story.
I just wonder if he's going to end up as the older aunt or maybe do a last minute switch with the younger aunt.