Yumenikki is an Android game by caerux.co.ltd that takes you on a journey through the dreams of a hikikomori named Madotsuki. The game has a very dark atmosphere and there is no particular story or purpose. It is just a walking game that lets you explore the dream world.

As you walk through the dream world, you can interact with specific characters and collect "effects". The appearance of the main character changes with each "effect" collected. If you use the same "effect" again, you will return to your normal appearance. You can collect "effects" only in a room of 12 doors.

Overall, Yumenikki is a unique and intriguing game that offers an immersive and dreamlike experience. The game's dark atmosphere and lack of direction may not be for everyone, but if you enjoy walking games and exploring new worlds, this game is definitely worth checking out.