How Did I End Up Here?

We all know the story of Harry Potter and how he survived an attack by the most feared dark wizard of the age. Of how he destroyed that very same dark wizard by destroying Horcruxes with the help of his friends. He made an enemy of the entire Death Eater army, but there was one of those Death Eaters that was different. Why did Draco Malfoy do what he did? Why did he join them?...