*Note: I do not own Death Note. :3
A sharp rattling sound could be heard coming from the kitchenette late that night. It was Light Yagami, who had snuck into the hotel room where L happened to be staying that night. Light immediately tried to silence the noise, for he knew the scruffy genius detective never slept. Light snickered and thought to himself, This would be the prank to end all pranks! Sure, he was being a bit childish, but that was how he was. As quietly as he could, Light pulled a large container of salt down from the top cabinet, where no one but the other task force members ever went. Then, Light reached for a large crate next to the refrigerator and removed a box of sugar cubes. Light carefully wet the end of his index finger under the faucet and pulled out the first sugar cube. Dampening the surface ever so slightly, he then rolled the sugar cube in a handful of salt taken from the container. After a moment of carefully shaping it, the cube was flawless and Light replaced it in the box. Cube after cube, Light continued to meticulously coat every one in salt. By the time he was finished, it was nearly dawn, so Light carefully closed the box, placed it back in the crate, and left without a sound.
Several hours later, Light returned to the hotel with his father, Soichiro, to work on the Kira case. L was sitting awkwardly at his computer, his knees up to his chest, as always. He leaned in closer, hunching his back. His constant companion, Watari, entered the room carrying a pot of coffee, a cup, a spoon, and a box of sugar cubes on a tray. Light smirked to himself as he watched L pour himself a cup of coffee and then idly began stacking sugar cubes as it cooled. L stared at his computer, tapping in what appeared to be crucial information, then reached for the top "sugar" cube on his tower. He held it between two fingers for a split second, then popped it in his mouth. And instant later, L spat the sugar cube onto the floor, jumped up, and whipped around to glare at the task force snickering behind him. Light stared at him expressionlessly, but was only able to keep his poker face for a few seconds after he saw the disgusted look on L's face. His mouth began to twitch, then he smiled and began to laugh.
"Pffffft Hahahahaha!!" he laughed, "I can't believe I got you! Hahahahaha!!" L stared as Light recovered from his laughter after a few minutes. Light looked at L, who stared at him blankly. "C'mon, can't you take a joke?" Light asked with a grin. L sighed, then cracked a small smile.
"Yes, I can. I suppose that, from everyone else's point of view, it was rather humorous." L said.
"I'm glad. And don't eat the rest of those, I'll get you a new box." Light said jauntily as he started toward the kitchenette, satisfied.