The shock of that contact froze him to the spot, sable eyes swirling with all sorts of emotions that he didn't really want to face. Severus merely watched her talk, make her point, and then close off just as he had. It seemed that they would never evolve beyond this: one step forward, three steps back.
"Lily..." he tried, but then forced himself to snap out of it and let his hand pull tightly against his bag, the place where she'd touched him tingling pleasantly, "See you, then." He gave her one last glance before forcing himself to turn away, shoulders hunching and eyes staring at the ground. He looked every bit the broody bat that he was always being described as, stalking away as fast as he could.