Patrickitis 

A mental disorder characterized by constant, intense impulses to practice the violin whenever possible. In early stages, subject exhibits abnormal affection for his instrument, and occasionally speaks to it. Subject slowly begins to stray from social activity, until, in the final stages, subject lives almost his entire life within an auditorium, gymnasium, or other such structure where constant practice of the violin is possible. Subject may also exhibit a tendency to lash out at those who do not have the disease,as well as appear tired and overworked, occasionally having dark circles form around his eyes. Almost always, and irrevocably, fatal.

D.J. spends all his free periods practicing in the auditorium! He must have Patrickitis.

Patrickitis by Amaxing (Who else?) December 9, 2007