What is the relationship between Tod and Luz in book scrawl?

There is no character named "Tod" in the book "Scrawl" by A.S. King. The story centers around the relationship between Luz, a teenager with a vivid imagination, and her new stepbrother, Finn.

It's possible you're thinking of a different book, or have misremembered the name. Could you provide more context or details about the character you are referring to?