If you really has the meaning of the name, Doktor Caligari nor Doktor Masaki, Der Sandmann you mast be.
Is she an ubume, a Japanese ghost of a woman who had died in childbirth, a decomposed body Ono no Komachi it was, her belly having grown.
To lose his mind, dreaming on dreaming on dreaming, to lose his mind. Or, to lose his mind, Yumeno has dreamt on his dreaming, and lose his mind again.
An embryo dances, but it has not been born, it's still in his mother's.
For Ichiro Kure, a dream is the key that opens all doors for the sane.