When one guardian falls, another must take their place. The newest recruit, Albion Nisbett, finds out that the job involves keeping a secret hidden just beneath the pavements of London. Magic is everywhere. You just have to listen closely.
It could just be me, but this stands out among the rest of your jaw-dropping description as being a little weaker. I know you can make this stronger and more concise!
Devin was the one who had given her a new name. She didn’t know what his actual name was, but he had introduced himself as Devin and told her within the first ten minutes of meeting her that she needed a new name to go by. Devin was tall with limbs that looked too long for the rest of him and a mop of thick, dark hair that got everywhere. He was a few years older than her, fiercely protective and the only other person she’d found who didn’t treat her like she was mad.
And here, you can return to the main character with a modifier to return us to her. "the girl" (or definitely something more colorful) to bring us back)
Others choose each word meticulously, plucking them like individual strings to weave harmonies of sound together; and others never even know that they have chosen. Sometimes, the words choose themselves.