Sai certainly knew how to move when he wanted to. If Usopp hadn't had such good practice at running, he might have been left behind, and he was a little surprised at how easily their new companion seemed to keep up.

"The sword was from the alchemists?" Usopp guessed, while preparing himself as per Sai's suggestion. There wasn't much to do... but he still took a couple of flour bombs and some of the game pieces, tucking them with his slingshot in his waistband. He still owed Sai a--a something. If not a short sword, then at least something like it. Well, who knew what kinds of useful things would be in the janitor's closet?

He also took out his notebook, flipping to the map. "It should be across the hallway, past the Sun Room opening upstairs." Then he tucked that away too, his hands free for his flashlight and in case he needed to grab his slingshot quickly.