Snape Agrees to Make the Unbreakable Vow
Pages 34-37
After Narcissa begs for Snape's protection of Draco, she requests that he make an Unbreakable Vow. Snape agrees, and Bellatrix, astonished by his willingness, acts as the Bonder. As the vow is made, a magical flame binds their hands, ensuring that Snape will protect Draco and even fulfill Draco Malfoy's Mission if he fails.
