The clown in Twelfth Night who sings “O Mistress Mine” is Feste.
Feste serves Olivia’s household, but he is more than a conventional comic servant. As a licensed fool, he can speak truths that other characters avoid, using songs, riddles, wordplay, and apparent foolishness to expose their self-deception. In Act 2, Scene 3, Sir Toby Belch and Sir Andrew Aguecheek ask him to sing the love song “O Mistress Mine.”
The song’s message—that youth and love should be enjoyed while they last—echoes the play’s themes of desire, disguise, and the instability of romantic judgment. Feste’s musical role also gives Twelfth Night a distinctive atmosphere: songs interrupt the action and deepen its emotional mood rather than serving only as jokes.
A frequent mix-up is with Bottom, Jaques, and Touchstone. Bottom belongs to A Midsummer Night’s Dream, Jaques to As You Like It, and Touchstone also to As You Like It. Feste is specifically Olivia’s fool in Twelfth Night, and “O Mistress Mine” appears in Act 2, Scene 3.