The Trash Can Feeds a War God

An ordinary woman finds an iron bucket that connects her world to an ancient border fortress. On the other side, a famed general is trapped by invaders and corrupt officials, his troops starving. She sends supplies; he sends back treasures that help her build a business and stand up to scheming relatives and merchants. As they grow closer, her modern resources help him fight for his kingdom. But when they try to reach through the passage, it seals shut. Can they find each other again?