Moon madness is an emotion and/or reaction characteristic of demons that results in a demon in Limbo on the island of Hybras to be yanked out of their time and into the spacetime continuum to drift eternally between dimensions and times.
Once a demon or imp experiences this feeling, he or she is no longer in control. This only happens near the magical space/time crater on the island Hybras. Silver will ground demons in a single dimension and time if they are in contact with it. It also makes the imp or demon want to jump into the crater and go to the human world, even though most die or end up on the moon and suffocate -- almost nobody has survived this.
Two known survivors of the time/space travel after being seized by moon madness are Leon Abbot and the imp No 1, both who were grounded in a single dimension and time by humans with silver.