Alliance Arts and co-developer WHO YOU have officially launched the demo version of their unique rhythm game, Yunyun Syndrome!? Rhythm Psychosis, on the Steam platform. This is a golden opportunity for players to sample the addictive blend of strains of denpa song and kaibunsho (an absurd narrative about the spread of mysterious posts).
Yunyun Syndrome Demo Details
Version demo Yunyun Syndrome!? Rhythm Psychosis You can already download and play through Steam for a limited period, starting from October 10 to October 31, 2025.
This demo content offers a play experience of about 30 minutes that includes the early part of the game. You will be able to experience first-hand gameplay loop which combines intense rhythm sessions with narrative adventure sections. More than 10 tracks, including some hidden tracks, are also available to play in this demo.
You will be able to experience first-hand gameplay loop which combines intense rhythm sessions with narrative adventure sections. More than 10 tracks, including some hidden songs, are also available to play.
As an important note, Alliance Arts confirmed that while the full release version will feature full voiceovers from Q-chan (Nanahira) and Yunyun (Haruko Momoi), some voice parts in this demo version have not been included.
Read also: Trying out Yunyun Syndrome at TGS 2025: Rhythm & Delusion
Participation in Steam Next Fest and Music Video Parade
Along with the demo launch, Alliance Arts also confirmed that Yunyun Syndrome will be part of the Steam Next Fest starting on October 14.
To add to the excitement, karaoke-style music videos of the in-game songs will be uploaded daily for five consecutive days on Alliance Arts official YouTube channelevery night at 21:00 JST.
Unique Narratives and the World of Yunyun Denpa Syndrome
Yunyun Syndrome takes you through the story of Q-chan (CV: Nanahira), the girl hikikomori who is obsessed with a 2D character named Yunyun (CV: Haruko Momoi). Through the rhythm of music, Q-chan spreads mysterious writings that slowly begin to corrupt and change the order of the real world.
This game is described with the tagline Denpa song × Kaibunsho × Rhythm game, presenting the story in a nuanced dark-pop that is distinctive and promises several endings (multi-ending).
Gameplay that Blends Rhythm and Story
The essence of Yunyun Syndrome is gameplay rhythm. Its uniqueness lies in tracklist which consists entirely of songs denpa song. This genre of music is known for its super-fast tempo and absurd lyrics, challenging your finger dexterity.
Iconic tracks like "Sakuranbo Kiss ~Bakuhatsu da mon~" and "Miko Miko Nurse - Ai no Theme" are confirmed to be among the more than 30 songs prepared for the full version. Each rhythm session you complete will propel the narrative forward, revealing more of the mystery behind Q-chan's condition and the world gone awry.
Release Schedule
The full version of Yunyun Syndrome! Rhythm Psychosis is scheduled to release in Winter for the PC platform via Steam.
To ensure a wider range of players, the game will support multiple languages, including Japanese, English, Mandarin (Simplified & Traditional), and Korean.
While waiting for more information, try out the demo and add this game to your Steam A wishlist is the best way to make sure you don't miss out on the latest updates around Yunyun Syndrome.
Source: official press release
