Severus had kept mostly to himself during his year and three months in the village, socialising only under the penalty of something more dire (typically the threat to hunt him down and drag him out of his house, but occasionally an added dose of even more concern was enough to give him a reason to reassure the few who cared that yes, he was still breathing, unfortunate as it was). He attended mass events as a duty rather than something he enjoyed, and in a trend that mirrored his real life, he had few friends and even fewer he felt comfortable confiding in.
Harry Potter was not one of those people. He hadn't been in his earlier incarnations, nor would he be now. Severus had gone this long avoiding any sort of heart to heart the Potter boy might have required to assuage his own guilt or whatever the reason might be; he had no intention of giving up that streak now. So when Harry walked into his apothecary on Monday, catching Severus' eye, he silently swore to himself and went about stirring his current creation. Five times counter-clockwise, with two and a half rotations in the opposite direction after a three second pause. Even if it hadn't been a potion that took up nearly all his concentration, he wouldn't have felt at all guilty about making Harry wait.
But at last he couldn't avoid him anymore, and finally he raised his chin from his position in the back of the shop, huddled over one of his cauldrons. "Each ingredient is labeled, Potter. Unless my suspicions all those years were correct, and you are in fact illiterate, you should be able to help yourself to whatever it is you need."