Joule possesses a unique ability known as the Muse, which gives her the power to manipulate the
minds of other adepts through the songs she sings as her alter ego, the virtual pop star known as Lumen.
When an adept’s brain is attuned to the same frequency as the songs sang by Lumen, their brain
activity becomes increasingly active, which as a result, enhances their septimal powers. When the
Sumeragi Group realized that any adept who can hear Lumen’s songs emitted brainwaves at a distinct
frequency, they began using Lumen’s power like sonar to pinpoint the location of adepts around the world.