The Black Swan has a different rune system from the rest of the Elvin world, allowing them to communicate secretly. Only Black Swan members who are taught the "key" to the cipher can read it. Sophie also has the ability to read these runes since she is the Black Swan's "Moonlark". Keefe uses them in his paintings when he gifted them to Sophie, so that she could read them. It is noted that he received assistance from Mr. Forkle while writing them.