Thieves and the Juvenile Myuu (盗賊と少年ミューに, Tōzoku to Shōnen Myū) is a book written by Mizuki Kurashina. It was yet to be publish and it's written at Augest 27, which is Ayame Kamijou's birthday and a few months before Marble's returns with the new death games in Real Account Tower.
The book features a boy named Myuu, who is a "living art" that captured by an millionaire since he is baby. The millionaire never teach Myuu anything nor even seeing the other humans except of the millionaire himself. Thus, Myuu has be living in a situation like this since forever. Until during Myuu was 10 years old, an thieves appeared in the millionaire's house to stealing things, this is also the first time Myuu seen an another humans other than the millionaire. When the thieves started to talks, Myuu is so scared at the language they used due to Myuu never learn to speak before. The thieves noticed Myuu can't talk and can't understand what they were saying, the thief boy find Myuu to be interesting and asked him joins with them. Myuu was scared at first but after think he can see the outside world he accepted the thief boy's invite and leave the millionaire's house.
After Myuu joined with the thieves, he want to say something to the thieves but he can't speak the language. Thus, the thieves teaches him one sentence "Thank you".
- The story is based on the story happened to Mizuki, Ayame and Yuuma Mukai during the Real Account Incident.
- The thieves is even based on both Yuuma and Ayame themselves.
- While the story is based on Mizuki's story, Chiho Fujimaki is not present in the book. Even Chiho herself wonder where were she in the book when she is part of Yuuma's group.