It doesn't make much to realize Sans isn't just wallflowering--and his hazy recollection of the missing people probably isn't 'oh, here they are, they're okay'.

He draws himself away from the crowds enough to stand close to the wall that Sans is at. He rests his back against it and folds his arms, barely containing his own frustration as he watches the crowd before slowly sliding his gaze to Sans--and giving him a once over.

"It does not suit you, I'm afraid." That uniform.