and he is betrothed to Raina, who falls in love with a mysterious man that hides in her room one night, the soldier Captain Bluntschli.  
The main character's disguise is almost given away when one of the central characters inadvertently blurts, "Oh!  The chocolate cream soldier!"  The servant Nicola is engaged to the servant Louka.  Both of them are servants to Catherine and Major Petkoff.  Sergius supplies the play's final words, "What a man!  Is he a man!" and he is betrothed to Raina, who falls in love with a mysterious man that hides in her room one night, the soldier Captain Bluntschli.  FTP, identify this drama by George Bernard Shaw that takes its name from the first line of Virgil's Aeneid.
The main character's disguise is almost given away when one of the central characters inadvertently blurts, "Oh!  
Arms and the Man