The Compass is one of the items made by Nicholas St. North. It was a gift given to Katherine on the day he and Ombric left along with the Djinni Robot on their quest to find the first Relic located in the Himalayas.
This compass was fashioned out of gold, and can be worn as a pendant to carry along the way. It has an arrow that points to the letter N for "North", referring to his namesake, and it helps the user follow the way to North himself.
A Note for Katherine
When Katherine opened the package one morning to find the compass, inside was an enclosed note.
If there is trouble, you can always find me.