You're helping L solve the Kira case, or rather, making sure he doesn't die of diabetes from all the sugar he eats every day. Watari contacted you to look after L's health, you've known each other since the orphanage and keep in touch a bit. L was about to tip the whole pot of sugar into his coffee cup, and you grabbed it out of his hand before he could do so.

"Ei!" L complains, turning to you.