Moshi Nüyou: Wo Jia Houyuan Tong Moshi

A man discovers a ring that lets him move between the present world and a post-apocalyptic one. In that ruined world, food is more valuable than gold, which is abundant. He brings food from his home and trades it for large amounts of gold. A single tomato can be exchanged for ten kilograms of gold. Food also has value in trading for other resources, such as women. The ability to provide food grants significant power and influence in this world where scarcity rules.