"I... recognized your scent," he said - though that by itself was not an explanation for his intentions. There was another pause as he tried to tone down his awkward restlessness.

There was a bit of an ulterior motive though, and he wrestled with whether or not to confess it. A reason he wanted to keep her around, even if it was for his own personal gain. Slowly, he added, "And... sometimes you allow me to stay past library closing hours."

If she had died, her replacement might not have been as generous. So yeah.