Breaking the Silence

Harry learned many rules growing up. Above all else he learned that the world did not want to hear him speak, so he decided to not waste his time doing so. When the young boy-who-lived makes it to Hogwarts will the resident Potion's Master be able to look past his own preconceived notions to break past Harry's self-induced silence? abused!Harry, Mentor!Severus, no current pairings