Japanese enka and kayokyoku singer Leon Niihama posted a music video for one of his double A-side seventh single songs, “Fun! Fun! Fun!,” on his official YouTube channel. The pop tune has been featured as the 73rd ending theme for the Detective Conan (also known in English as Case Closed) TV anime series since its 1158th episode aired in Japan on April 12.
Niihama previously sang “Tsukamaete, Konya,” the opening theme for the spin-off series Case Closed: The Culprit Hanzawa in 2022, but this is the first time that he has provided a theme song for the Conan anime’s main series.
Leon Niihama “Fun! Fun! Fun!” Music Video
Detective Conan Creditless 73rd Ending Video
Niihama made his debut as an enka (traditional Japanese ballad) singer in May 2019, releasing six singles date.
“I am very honored to be in charge of the ending theme for Detective Conan, an anime that is very popular worldwide beyond Japan,” said Niihama. “With respect for the historical anime and the joy of being in charge of the theme song, I have been working with the Detective Conan team since last summer to create this song. It is a fun song that everyone can dance to, and I would love to dance to it at events with the audience. ‘Fun! Fun! Fun!’ will make the world a little brighter and more cheerful!”
The double A-side CD single “Fun! Fun! Fun! / Honoo no KISS” is set to release in Japan with five editions tomorrow, April 16. Prior to the CD release, “Fun! Fun! Fun!” is now available on digital platforms for download and streaming.
Kokoro Odoleon edition CD jacket
Kirakira Hikaleon edition CD jacket
Moeagaleon edition CD jacket
Iroke Dadamoleon edition CD jacket
Detective Conan edition CD jacket
bonus acrylic stand for the Detective Conan edition
Meanwhile, Niihama and Kocchi no Kento, both of whom are in charge of the theme song for the spring 2025 TV anime, have each released collaboration videos on their official YouTube channels, singing their respective songs together. Kocchi no Kento’s latest song “Kekka Orai” is now featured as the opening theme for the spring 2025 TV anime My Hero Academia: Vigilantes.
Kocchi no Kento x Leon Niihama “Fun! Fun! Fun!” Collab Video
Leon Niihama x Kochi no Kento “Kekka Orai” Collab Video
The TV anime adaptation of the original Detective Conan manga by Gosho Aoyama began airing in Japan in January 1996, while the first theatrical anime film was released in April 1997.
Crunchyroll, which streams the TV anime series, describes Detective Conan:
The son of a world famous mystery writer, Shinichi Kudo, has achieved his own notoriety by assisting the local police as a student detective. He has always been able to solve the most difficult of criminal cases using his wits and power of reason.
Sources: Leon Niihama official YouTube channel 1, 2, Kocchi no Kento official YouTube channel
