
The Boy is a singer at Mariana's moated grange, and the play's only song is his. Act IV opens on him singing to Mariana "Take, O, take those lips away, / That so sweetly were forsworn", a lament for kisses that were "seals of love, but sealed in vain" - words that fit Mariana's own case, since Angelo broke off their betrothal when her dowry was lost at sea.
A boy who sings to Mariana at her moated grange at the start of Act IV - the play's only song - and leaves when the disguised Duke arrives.
He has no spoken lines. As the disguised Duke approaches, Mariana tells him to break off his song and go, then apologises to the Duke for being found "so musical": the music, she says, displeased her mirth but pleased her woe.
The Boy has no aim of his own in the text: he sings for Mariana and goes as soon as she sends him away.
The Boy is a voice rather than a character: his song sets the melancholy of the grange just before the Duke arrives with the plan that will send Mariana back to Angelo.