Late enough that Alma feels confident that the cafeteria will be mostly empty, even the kitchen staff working on a skeleton crew. Most of the Order is asleep, but Alma's found he doesn't need to sleep nearly as much as a human does, now. And night vision doesn't hurt his nighttime forays away from the labs, either.
He goes through the usual routine with the poor girl working the window ("Give me something I haven't had before" because he wants to try something new every day, because if he's stuck living then he might as well make the best of it), trying to not terrify her too much, and it seems to be working, mostly. Most people don't expect an Akuma to be cheery, or grateful, or any of the slew of positive emotions that humans (most humans, Alma corrects himself with some irony, counting on one hand the number of times he's seen Yu in a good mood) go through all the time. So he grins at the kitchen girl, and thanks her, hoping to defy their expectations a little bit more, to seem a little less unapproachable and frightening.
But like always, he goes to sit alone at a corner table, and when Alma is sure no one is watching, the smile slips, and he pokes at a pile of mashed potatoes with the tip of his tail, doodling random Chinese characters in his ever-sloppy "hand"writing.