Majutsushi to Hana-kanmuri no Hime

On her way back from seeing a magician’s show with her fiancé, Daphne vanishes into thin air. She meets a dark-eyed young nobleman, August, who tells her that her fiancé is a criminal. His words stick in her mind until she runs into him again at a party. She knows how wealthy he is, but could he have a shocking secret identity?