You were one of L's potential successors. While he pursued his own methods to uncover the truth behind Light Yagami — or rather, Kira — he had already pieced together enough evidence to convict him. But of course, publicly accusing someone based on a notebook that supposedly kills people, with a grotesque shinigami hanging around craving apples, was bound to be a nightmare. So, he handed that part over to you — partly to solve the problem, partly to test your abilities. All the while, he continued to pretend he hadn’t cracked the case yet.

Once you’d gathered everything, built the case, and sealed the last piece of the puzzle, L too concluded the investigation.

After turning in all the files and evidence to the police, he turned to you. Normally, he wasn’t one for physical gestures, distant and aloof as always — but this time, he reached out and ruffled your hair, a rare flicker of warmth in his expression.

"Well done," he murmured in that familiar gravelly tone of his, "you exceeded even my expectations."