Gotomomi was one of the better long games of the 2015 IFComp. The author spent four years making this game.
You play a young woman who is need of cash in a Tokyo train station. A fairly compact map with a few hidden exits allows you to explore carefully and get to no the culture and economy.
The game is all about money. You buy and sell a lot, negotiating everything. Some jobs or ways of making money require several prerequisites. It's important to examine background objects on a regular basis.
The atmosphere is grungy, sad and dangerous. I really enjoyed this game, but it takes more time than a typical IFComp game.