Captured in the bookshelf are pages from my past

The day we met, he came to pick me up at my place. He borrowed a book from my bookcase. It was Maximum City. At that point in the afternoon, I did not know if I was going to see him again, least of all marry him. And the book he borrowed from me was a gift. I did not want to lose it. So he offered to give me one of his, as a sort of surety - that his book would be mine for keeping, until he returned the one he had borrowed from me.