Japanese singer-songwriter Watashi Kobayashi released a single titled “Ningyou no Machi”. The song was announced as the ending theme for the television anime The Case Book of Arne, which was airing at the time of the original announcement. An official music video accompanied the release.
The press materials linked the anime’s official website and confirmed that the music video for “Ningyou no Machi” was publicly available.
According to the announcement, Watashi Kobayashi wrote “Ningyou no Machi” specifically for The Case Book of Arne. He played the original game on which the anime was based and developed the lyrics and music around its story and setting.
Takeaki Wada handled the arrangement. This was intended to be more than a conventional promotional tie-in, with the composition reflecting the atmosphere of the source material.
Music video by Kuso Ryoriten Kani
The music video was released alongside the single. The press announcement credited Kuso Ryoriten Kani with its production and described it as an unusual animated work within Watashi Kobayashi’s music-video catalog.

The official Asmik Ace YouTube channel also published a creditless ending sequence for the anime, allowing viewers to hear the song alongside scenes from The Case Book of Arne.
Digital single and music video links
The original press information included official links for streaming the single and finding its music video.
Digital single: “Ningyou no Machi”
Stream or download “Ningyou no Machi”
About Watashi Kobayashi: musician, streamer, and writer
The original press profile described Watashi Kobayashi as a singer-songwriter with more than 340,000 followers across social platforms at the time. He was also active as a streamer and writer.
According to that profile, he was born on January 18, 1999, in Tokyo. He began pursuing music more seriously while attending Tama Art University and gained attention through videos of himself playing music in his room.

The press materials also reported more than 160,000 YouTube subscribers at the time. His discography included the fourth album Chuten wo Nozomu (HEROIC LINE, King Records), released in June 2024, and earlier anime tie-ins such as “Rinkaku” and “Sora ni Shimeyuu” for Ragna Crimson.
Official channels and additional information
Watashi Kobayashi’s official site and social accounts provide further information. “Ningyou no Machi” could be heard as a digital single, through the animated music video, or in the anime’s creditless ending posted by the official channel. For the anime’s opening theme, read Wordtura’s article on Sou’s “Q.E.D.”.
- Official website: kobayashiwatashi.com
- X: @koba_watashi
- YouTube: Official Watashi Kobayashi channel
- Instagram: @kobayashi_watashi_staff