E.T.A. Hoffmann 2
About the butterfly: butterflies can be found on ancient christian tombs as a symbol of death and resurrection, and here it can have the same meaning.
Or maybe there is a sort of connection with Julia Marc, the young girl with whom Hoffmann fell desperately in love at the age of 35 (she was 15 and he gave her singing lessons). In Hoffmann's diaries Julia is symbolised with a butterfly.