L has neither the time or the space to parse his own reaction to the pattern. At the moment, his one task is to handle Light, through the rather unique combination of deep respect and placation measures.

"Right... of course, we should probably clean it up for the next practicers."

It's not a lesson anymore, however. While Light could undo this given the time, it's not time L wants to give him, for complex reasons that go beyond simple disquiet or even anger. He crouches, spreading his fingers over the colors at his feet and appearing to pull them apart like tissue paper, leaving a blank and dull floor beneath them. Around them, the illusions on the walls appear to melt into the baseboards.