I'm also a sucker for a man who will drive a whole box of soap (and said packaging) halfway across the country for me, just because he used some once while visiting me and wanted to replace it.
I think the scent reminds him (and me, if I'm being honest and uncharacteristically nostalgic) of a particularly exciting time in our relationship. The long-distance phone calls. The agonized-over mixed CDs. Pre-"I love you" and "I think I want to move to North Carolina." It reminds me of all the places we both love (and left behind) in Oklahoma City, and the adventures we had there before I moved.
And it reminds us both to take showers occasionally.