Sin is a rock star. He has an amazingly loud voice with a range of four octaves. His secret is that he has created his voice through a method of vocal cord doping. His voice is now teetering on the edge, due to side effects from the vocal cord doping. Around this time, Sin meets Fūka, who is a street musician. When Fūka sings, her voice is so small. Due to Fūka, Sin looks back upon his past.
Unfortunately the movie LOUDER! Can't Hear What You're Singin', Wimp! is not yet available on HBO Max.
| Sound | Koji Ueno | Original Music Composer |
| Writing | Satoshi Miki | Screenplay |
| Art | Toshihiro Isomi | Production Design |
| Editing | Masahide Kôra | Editor |
| Camera | Daisuke Soma | Director of Photography |
| Production | Yusuke Wakabayashi | Producer |
| Art | Emiko Tsuyuki | Production Design |
| Production | Toshiyuki Okuma | Production Manager |
| Production | Takuya Kitazawa | Production Manager |
| Visual Effects | Shinji Ohagi | VFX Supervisor |
| Directing | Satoshi Miki | Director |
| Art | Masato Nunobe | Set Decoration |
