L's new position is slightly less approachable than the one before it, and Cesar opens and closes his hand once L is no longer holding onto it, looking at L's shoulder. He could grasp it. He could...

... do nothing of the sort at all. His gaze drops to the floor, and his hand moves back to his side. He nods a little, tugs his mouth into a weak, unhappy smile, and then turns to the door. L latched every lock it had in a frenzy, and it felt as though there were enough to keep out an entire army, but now it's just a door. Two locks, and the sliding door-catch. Cesar undoes them and opens the door.